The Note's Must-Reads are a round-up of today's political headlines and stories from ABC News and the top U.S. newspapers. Posted Monday through Friday right here at www.abcnews.com

Compiled by ABC News' Carrie Halperin, Amanda VanAllen and Jayce Henderson

NORTH KOREA USA Today's Aamer Madhani and Tom Vanden Brook: " Reports conflict on North Korea's nuclear capabilities" With newly-revealed U.S. intelligence showing that North Korea may already be able to arm a missile with a nuclear warhead, President Obama said on Thursday that North Korea must end its "belligerent approach." After meeting with U.N. Secretary-General Ban Ki Moon at the White House on Thursday, Obama said they both agreed that it was time to "lower temperatures." "Nobody wants to see a conflict on the Korean peninsula," Obama said. "But it's important for North Korea, like every other country in the world, to observe the basic rules and norms that are set forth, including a wide variety of U.N. resolutions." LINK

Bloomberg's Roger Runningen: " Obama Says North Korea Must End Its 'Belligerent' Tone" President Barack Obama said the time has come for North Korea to end its "belligerent approach" and vowed the U.S. would defend its interests and those of its allies in the region. Obama told reporters before a meeting today with United Nations Secretary General Ban Ki-moon that the North Korean regime should "lower temperatures" of its rhetoric to avoid a conflict on the Korean peninsula. LINK

GOP The Boston Globe's Jim O'Sullivan: " GOP Senate debate gets personal" The three Republican candidates for US Senate unpacked their opposition research files Wednesday night, rifling through each other's careers for damaging information and flinging accusations during the primary's second televised debate. LINK

GUN CONTROL The Wall Street Journal's Kristina Peterson: " Senate Gun-Bill Debate Begins After Hurdle Overcome" The Senate voted Thursday to begin the process of bringing gun-control legislation to the floor, entering a new stage of the national debate over gun violence four months after an elementary-school shooting in Newtown, Conn.A bipartisan group of lawmakers defeated a GOP attempt to block the bill from coming to the floor. Sixteen Republicans joined all but two Democrats in the 68-31 vote to advance the legislation, clearing the way for the Senate to likely begin considering amendments early next week. LINK

The New York Times' Jennifer Steinhauer: " Senators Agree to Start Debate on Gun Safety Measures" Pressed by shooting victims and relatives of Americans slain in gun violence, the Senate on Thursday voted to begin an emotionally and politically charged debate on gun safety proposals as advocates of new laws overcame a Republican filibuster threat. The strong majority in favor of considering legislation that would expand background checks and increase the penalties for illegal gun sales reflected the power of a lobbying campaign by parents of students killed in Newtown, Conn., and by others who persuaded reluctant lawmakers to back them in an initial fight that looked lost just last week. LINK

The Washington Post's Philip Rucker and Paul Kane: "Growth of suburbs in pro-gun states changing the political calculus in Congress" Pennsylvania, Georgia and Virginia have long been bastions of gun-rights supporters, with vast rural areas and strong hunting traditions. But in recent days, lawmakers from those states have demonstrated a new willingness to back stricter firearms regulations, setting the stage for what could be the first major gun-control legislation to pass Congress in two decades. LINK

IMMIGRATION Politico's Jake Sherman and Kate Nocera: " Conservatives lash out at immigration reform" A pocket of conservatives is lashing out privately and publicly against broad immigration reform and could seriously complicate any momentum for a House deal. The blowback began in earnest Wednesday afternoon on Capitol Hill, where a meeting of the Republican Study Committee turned into a group gripe about the direction in which a bipartisan House group of immigration negotiators is heading. LINK

CITIZENS UNITED ABC News' Anjuli Sastry: " Universities Join Effort to Overturn Citizens United Decision" Students at the University of California at Berkeley will vote on a referendum this week as part of an effort to convince the U.S. Supreme Court to overturn its controversial 2010 Citizens United v. Federal Election Commission decision nearly three years after the original ruling. According to the decision, political spending to support individual candidates constitutes a form of protected speech under the First Amendment, and the federal government cannot deny corporations or unions the right to spend. LINK

ABC NEWS VIDEO: " Medal of Honor Awarded to Korean War Army Chaplain" LINK " Michelle Obama's Emotional Plea for Gun Control" LINK

BOOKMARKS The Note: LINK The Must-Reads Online: LINK Top Line Webcast (12noon EST M-F): LINK ABC News Politics: LINK George's Bottom Line (George Stephanopoulos): LINK Follow ABC News on Twitter: LINK ABC News Mobile: LINK ABC News app on your iPhone/iPod Touch/iPad: LINK