The Note: Biden deepens policy fault lines in Democratic primary

THE TAKE with Rick Klein

Former Vice President Joe Biden launched his candidacy by vowing to adhere to a version of Ronald Reagan's famous "Eleventh Commandment."

"Never speak ill of another Democrat," Biden told ABC News' Robin Roberts.

Whether he sticks to that through a long and crowded campaign is the question. Biden is already directly challenging his rivals in ways that are likely to exaggerate the party's policy fault lines.

That starts with a campaign tone that emphasizes union support and "people being able to work with their hands," he said Tuesday in Iowa, as part of a campaign swing there that continues on Wednesday.

It's already moving into policy. Biden is arguing that "we have to finish the job" on health care -- that is, build on Obamacare and not replace it with Medicare for all.

"You can buy into the system," Biden told ABC News. "But not Medicare across the board for everyone and eliminate private insurance."

Biden may not want to engage directly with the other 19 Democrats running for president, but where will he land on the Green New Deal? Wealth taxes? Free college?

The other candidates have spent enough time debating policy in his absence that he has invited distinctions that will become disagreements.

THE RUNDOWN with MaryAlice Parks

Attorney General William Barr likely will face questions on just about every major headline out of Washington these last few months when he takes the hot seat in front of the Senate Judiciary Committee on Wednesday.

But a headline late Tuesday likely jumped to the top of lawmakers' lists: Several news outlets, including ABC News, reported that special counsel Robert Mueller expressed frustration to the attorney general over the public's interpretation of his investigation when Barr issued a four-page letter describing the report's "principal conclusions" within 48 hours of receiving the special counsel's findings.

Tuesday afternoon, a group of 12 senators urged the Department of Justice Inspector General to investigate several matters related to Barr's impartiality in handling the special counsel's probe. In a letter, they openly questioned whether he could credibly supervise the 14 criminal matters that have stemmed off from Mueller's investigation.

Expect some wildcard headlines to emerge from the hearing, too. For example, a group of Democrats on Tuesday introduced a bill they said was designed to "directly combat" Barr's efforts to "indefinitely detain immigrants."

More, congressional eyes will be trained on Barr's response to President Donald Trump's latest decision to stonewall and fight all subpoenas and investigations from Capitol Hill, including those related to his taxes, finances and workings beyond what Mueller investigated. The attorney general could be asked -- by this president -- to have teams defend that staunch position in court. Is Barr up for that?

THE TIP with Lissette Rodriguez

In just under two months Democratic presidential candidates will take the debate stage for the first time, but that isn't stopping Sen. Bernie Sanders and Biden from sparring on one of their signature talking points: the economy.

On CNN Monday night, Sanders said voters would see clear differences between them when it comes to their Senate voting records on topics like the North American Free Trade Agreement.

"I helped lead the fight against NAFTA. He [Biden] voted for NAFTA," Sanders said. "I like Joe Biden, Joe is a friend of mine. But I think what we need to do with all of the candidates [is] have an issue-oriented campaign, not personal attacks."

By Tuesday afternoon Biden had a response for his former Senate colleague: "I'm going to have plenty of time to get into debates about NAFTA. I'm not a free trader, I'm a fair trader."

THE PLAYLIST

ABC News' "Start Here" podcast. Wednesday's episode features ABC News Chief National Affairs Correspondent Tom Llamas, who walks us through a violent and chaotic day in Venezuela. Then ABC News' Trish Turner previews Attorney General William Barr's upcoming testimony on Capitol Hill following the release of the full Mueller report. http://apple.co/2HPocUL

ABC News' "Powerhouse Politics" podcast. Political Director Rick Klein and Deputy Political Director MaryAlice Parks speak with FivethirtyEight's Nate Silver about the layout of the 2020 race, and how former Vice President Joe Biden's entry changes the landscape. https://apple.co/2Zfz5nD

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