By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• BREAKING - U.S. CONDUCTS AIR STRIKE IN IRAQ: A statement from Pentagon Press Secretary Rear Adm. John Kirby: "At approximately 6:45 a.m. EDT, the U.S. military conducted a targeted airstrike against Islamic State of Iraq and the Levant (ISIL) terrorists. Two F/A-18 aircraft dropped 500-pound laser-guided bombs on a mobile artillery piece near Erbil. ISIL was using this artillery to shell Kurdish forces defending Erbil where U.S. personnel are located. The decision to strike was made by the U.S. Central Command commander under authorization granted him by the commander in chief. As the president made clear, the United States military will continue to take direct action against ISIL when they threaten our personnel and facilities."

• WHAT OBAMA SAID: President Obama said last night he has authorized "targeted" air strikes if necessary to protect American interests in Iraq from insurgent forces that are taking over the country's northern cities. If the terrorist group ISIS reaches Erbil, the president said he will call in U.S. air strikes. The U.S. has an embassy and other staffers in the city. Air strikes have also been authorized to protect families fleeing ISIS in the Sinjar Mountains. "These innocent families are faced with a choice: descend and be slaughtered or stay and slowly die of hunger," he said. http://abcn.ws/1pFcVnz

• U.S. COMBAT TROOPS WILL NOT RETURN: "As commander in chief, I will not allow the United States to be drawn into fighting another war in Iraq," Obama said in a brief address at the White House last night. The announcements marked the deepest American engagement in Iraq since U.S. troops withdrew in late 2011 after nearly a decade of war. "Today, America is coming to help," Obama said. "The U.S. cannot turn a blind eye." An air drop of food, water and medicine made at the request of the Iraqi government has been completed, the president said in the statement from the White House. http://abcn.ws/1pFcVnz

THIS WEEK ON 'THIS WEEK': On Sunday, "This Week" covers the latest on the U.S. response to the escalating crisis in Iraq. Plus, the powerhouse roundtable debates all the week's politics, with ABC News' Matthew Dowd and Cokie Roberts, ESPN's LZ Granderson, and journalist and author Sharyl Attkisson. See the "This Week" homepage for full guest listings. Be sure to use #ThisWeek when you tweet about the program. Tune in Sunday: http://abcnews.go.com/thisweek

THE ROUNDTABLE

ABC's SHUSHANNAH WALSHE: It's officially a clean sweep. For the first time since 2008, this is the first cycle when no incumbent GOP Senator has lost a re-nomination fight. Sen. Lamar Alexander's victory last night marked the tea party's last stand this primary season and although it was a tighter than expected outcome at a nine point spread, the tea party came up short yet again. Despite the failure to topple a sitting Senator with millions of dollars unsuccessfully spent, it's unlikely we will see an end to insurgent challengers in each cycle. One victory they can claim, in addition to Eric Cantor's fall, is the ability to say they helped move the party to the right. Out of fear of being challenged or more pure reasons, the GOP has become more conservative and that's one win the tea party can rightfully claim and will continue to push for.

ABC's JEFF ZELENY: The week in Iowa politics opened with a three-day visit by Rand Paul and closes with a parade of Republican hopefuls, all eager to plant early seeds for their 2016 presidential aspirations. Ted Cruz is arriving for his second straight weekend. Rick Santorum and Rick Perry are back, too. And Bobby Jindal is bringing his whole family to the Iowa State Fair. Even for the most politically inclined, these trips may be coming a bit early. And there is a quiet sense of worry, among at least some Iowa Republicans we talk to, that the visits may not be entirely helpful to the biggest contest of the year: The campaign to fill Sen. Tom Harkin's seat. Joni Ernst has become one of the most promising Republican Senate recruits of the year, but as she tries to create her own persona, will having Cruz and the gang tagging around make it more difficult?

WHAT WE'RE WATCHING

ABC'S '14 FOR 14- HOT SEAT: MEET MARY BURKE, WISCONSIN GOV. SCOTT WALKER'S WORST NIGHTMARE. Democrat Mary Burke is statistically tied in the latest polling with Wisconsin's Republican Gov. Scott Walker, who is often discussed as a possible contender for his party's nomination for president in 2016. Burke, a Democrat whose family owns a successful bicycle business, is hoping to play spoiler in one of the most closely watched head-to-head races in the country this November. Recent polling from Marquette University Law School shows her with a one-point edge among likely voters, and within one point of Walker among registered voters. The Wisconsin governor's race is part of ABC's "14 for 14? project, which is tracking key contests across the country between now and November. ABC's JOHN PARKINSON recently conducted a rapid-fire question/answer session with Burke, delving into the candidate's thoughts on a range of topics, from her ties to Hartland, Wis. to forgiveness for future Packers Hall of Fame quarterback Brett Favre. http://abcn.ws/1pZ7ZHz

BUZZ

with ABC's SCOTT WILSON

TENNESSEE SEN. LAMAR ALEXANDER DEFEATS TEA PARTY CHALLENGER JOE CARR. Incumbent Tennessee Sen. Lamar Alexander won his primary last night, defeating tea party challenger state Rep. Joe Carr in the Republican primary, ABC's SHUSHANNAH WALSHE reports. With 100 percent of precincts reporting, Alexander bested Carr 49.7 percent to 40.5 percent, according to the Associated Press. This was a tighter than expected final outcome. Self-funding candidate and Memphis radio station owner George Flinn came in with 5.2 percent and there were four other lesser-known challengers. This race marked the tea party's last best chance to beat an incumbent senator and with Alexander's victory, it marks the end of months of trying, as well as millions of dollars spent, to oust a sitting senator by an insurgent intra-party challenger. They tried in Kentucky, Texas, South Carolina, Mississippi, and earlier this week in Kansas, but came up short each time. Despite the effort and dollars spent, this will be the first cycle since 2008 when no incumbent GOP senator has lost a re-nomination fight. Unlike many of those other races, this one didn't get the support of several outside conservative groups like the Senate Conservatives Fund, which pledged to toss out incumbent senators in other races but were unsuccessful. http://abcn.ws/1sDbacK

IOWA CANDIDATE: 'PRESSURE IS ON' IN SENATE CONTROL BATTLE. DES MOINES-At the dawn of the midterm election season, when Republican dreams of winning control of the Senate still seemed distant, the open seat in Iowa was barely on the radar of the marquee races to watch, ABC's ARLETTE SAENZ and JEFF ZELENY note. But with only three months of campaigning to go, it's not an overstatement to say Democrats now worry that their ability to retain the Senate majority hinges to a large degree on the outcome of the race in Iowa. Rep. Bruce Braley, the Democratic nominee, has struggled to meet lofty expectations and is now locked in a tough contest with Joni Ernst, a Republican state senator. "The pressure is to make sure Iowa voters understand the clear choice they have in this election between me and my opponent because of the huge impact it's going to have on their future," Braley told ABC News on Thursday at the Iowa State Fair. He did not dismiss the suggestion he's the underdog in the race. "I've always felt like when you're running in a race in a state like Iowa, you're the underdog because this is a very purple state," he said. http://abcn.ws/1om1iml

CANDIDATES USE HOLLYWOOD SOUNDS TO WOO VOTERS. Politics rarely resembles the interpretation of government that Hollywood, or Netflix for that matter, presents to the public. Every now and then though and especially during campaign season, the two worlds coalesce. It is not unusual to find celebrities endorsing political candidates and even donating campaign funds. What is unusual is a candidate using the soundtrack of a Hollywood blockbuster as background music for their television ad, notes ABC's CALEB JACKSON. One quick glance at this ad from Tennessee state Representative Charles Sargent, and you may recognize the romantic, somewhat patriotic tune in the background. It happens to be the theme song from "Dances with Wolves," the 1990 Western starring Kevin Costner. No word on whether Sargent has paid for the rights to use the track or why he chose the soundtrack from a film about a man befriending wild wolves. ABC News tried reached out to Sargent for comment on his exquisite taste in cinema orchestration, but he never responded. http://abcn.ws/1kpWNqX

HERE'S HOW BADLY COLUMBUS, OHIO WANTS 2016 DEMOCRATIC CONVENTION. Forget the red carpet-Columbus, Ohio, is rolling out the blue. With a team from the Democratic National Committee in town to consider the central Ohio city as a possible site for the 2016 Democratic National Convention, residents and city leaders are pulling out all the stops, according to ABC's JENNIFER HANSLER. Thursday was the city's last chance to impress the DNC. The day's itinerary was meant to showcase Columbus' "championship culture," according to the Columbus Dispatch. Delegates will tour Ohio Stadium, the home turf of the Ohio State Buckeyes, and may meet with coach Urban Meyer. With the visit to the venue, organizers hope to woo the selection team with the idea of a presidential nominee accepting the nomination there in front of a crowd of 100,000. And on Wednesday, the city actually staged an entire parade and rally outside of Nationwide Arena to welcome the DNC's site selection delegation. http://abcn.ws/1lEsckG

MONTANA SEN. JOHN WALSH ABANDONS SENATE RACE AFTER PLAGIARISM SCANDAL. Sen. John Walsh, Democrat of Montana, is abandoning his fall election bid in the wake of a plagiarism scandal that shook his campaign late last month, reports ABC's JEFF ZELENY. "The 2007 research paper from my time at the U.S. Army War College has become a distraction from the debate you expect and deserve," Walsh said in a statement. "I am ending my campaign so that I can focus on fulfilling the responsibility entrusted to me as your U.S. Senator. You deserve someone who will always fight for Montana, and I will." "It is time for us all to return to the real issues of this election," he added. Walsh intends to serve out the rest of his appointed term, one official tells ABC News. He has been under heavy pressure to leave the race, including calls from party officials and editorials in his state's newspapers. http://abcn.ws/1u2EtXU

OBAMA SIGNS VA REFORM BILL. President Obama signed the new veterans' reform bill Thursday, signing into law one of the few bipartisan legislative accomplishments of this Congress, notes ABC's BENJAMIN SIEGEL. The reform bill, enacted in response to revelations of poor care and long wait times at veteran care centers across the country, will provide the facilities with greater resources while adding oversight to the Department of Veterans' Affairs healthcare system. Eager to show progress on a crisis that drew sharp criticism for his administration, Obama said the bill would address the problems discovered at facilities. "Working together, we set out to fix [problems at VA facilities] and do right by our veterans across the board, no matter how long it took," Obama said. http://abcn.ws/1vhwXu1

CDC: UNCLEAR WHETHER EXPERIMENTAL EBOLA SERUM WORKING ON AMERICANS. As two American relief volunteers infected with the Ebola virus make "slow improvement" at an Atlanta hospital, the director of the Centers for Disease Control and Prevention told Congress that even with a full recovery it will be impossible to know whether an experimental drug has had any impact on their health, ABC's JOHN PARKINSON reports. Lawmakers convened a rare summer hearing today to examine the international community's response to the outbreak across West Africa, as well as deliberate whether ZMapp, an experimental serum mixture of three antibodies, could help stem the deadly outbreak if it was more widely available. "The plain fact is that we don't know whether that treatment is helpful, harmful or doesn't have any impact," Dr. Tom Frieden testified. "We're unlikely to know from the experience of two or a handful of patients whether it works." "If there's a new treatment, we will do everything we can to help get it out to those who need it most," Frieden said. "But right now, we are months or at least a year away." http://abcn.ws/V2cfh5

IN CASE YOU MISSED IT

MISCHIEVOUS TODDLER TRIGGERS WHITE HOUSE LOCK DOWN. Well, this might be a first. The White House was temporarily locked down Thursday night as Secret Service responded to a unique incident on the North Lawn. Fence-jumpers are a frequent occurrence here, but not like this, notes ABC's MARY BRUCE. A toddler apparently squeezed through the north fence, triggering security alerts and causing agents to race across the lawn. Per protocol, the White House was locked down, Pennsylvania Avenue was closed, and the gates were shut. The toddler, who no doubt was terrified by the ordeal, has since been reunited with his parents. "We were going to wait until he learned to talk to question him, but in lieu of that he got a timeout and was sent on way with parents," Edwin Donovan, spokesman for the US Secret Service, said in what will go down as one of the best press statements of the year. Just another night at the White House… http://abcn.ws/1kq1UY6

WHO'S TWEETING?

@russellberman: The #Benghazi Select Committee is 3 months old today. It has yet to hold a hearing, but that will change in Sept. http://www.thewire.com/politics/2014/08/whatever-happened-to-the-benghazi-select-committee/375748/ …

@nprpolitics: 40 years ago today, President Nixon resigned amid #watergate scandal Linda Wertheimer @npr remembers: http://n.pr/V3IxIz @morningedition

@mikiebarb: On A1 today, my look at how GOP presidential hopefuls are wooing Hispanics by turning to Latin America: http://mobile.nytimes.com/2014/08/08/us/politics/potential-gop-presidential-candidates-woo-hispanics.html?_r=0&referrer= …

@maggiepolitico: A Clinton neighbor in their "slumming it" rental of an $18 mill home in the Hamptons has a birds-eye view http://m.huffpost.com/us/entry/5652456 …

@moody: Mitch McConnell's wife sits on the board of a group working to kill the coal industry. http://yhoo.it/X6gzh1 #KYSen