The TAKE with Rick Klein

A president running on "law and order" needs his law man -- now, perhaps, more than ever.

Enter Attorney General William Barr, who testifies on Capitol Hill Tuesday for the first time in 15 months. His first appearance before the House Judiciary Committee during the Trump presidency could also mark his last such testimony before the election.

Of course, though, President Donald Trump's second Senate-confirmed attorney general hasn't gone anywhere. Barr has been practically everywhere, and now finds himself in the center of converging political dynamics that could be key to Trump's reelection hopes.

Consider just some of the storylines he's been at the center of during his year and a half on the job: the Mueller report, Ukraine and impeachment, Lafayette Square, Michael Flynn, Roger Stone, Michael Cohen, Geoffrey Berman, the president's voter-fraud claims, the origins of the Russia probe, deployments in Portland and now, "Operation Legend."

All that and more could be covered by Democrats on Tuesday -- even while some talk about impeaching him, and Republicans rally behind him as a conservative hero who is defending the Trump presidency.

“From my experience, the president has played a role properly and traditionally played by presidents" regarding Justice Department matters, Barr will tell lawmakers, according to his prepared opening statement.

Barr's expansive views of federal power could be key from here. Trump has been openly mulling executive actions on immigration and health care, and is threatening to send federal agents into more cities to quell violence -- with explicitly political overtones, as he warns of what might come in a Biden presidency.

Just five months, but also a thousand years ago, Barr made a rare public plea for Trump to tone it down when it comes to Justice Department commentary. He told ABC News Chief Justice correspondent Pierre Thomas that Trump tweets about his department's work "make it impossible for me to do my job."

The tweets haven't stopped, and the political stakes are only higher now. No one is expecting Barr to break with the president, but his answers on Capitol Hill and in courthouses could prove pivotal down the line.

The RUNDOWN with MaryAlice Parks

So much for that supposed rhetorical reset from the president on the coronavirus. After looking to turn a page and offer a more serious and sober take on the crisis last week, Trump instead on Monday continued with his rather absurd focus on how the number of confirmed cases of COVID-19, in his view, makes the United States look bad -- rather than reflect on how improving the country’s testing capabilities would help us understand how the spread of the virus in the U.S. has far outpaced that in almost all other wealthy nations.

The president went on to again undercut the advice of his own scientists and White House experts, adding Monday in North Carolina, "I really do believe a lot of the governors should be opening up states that they're not opening and we will see what happens with them."

The last few weeks White House Coronavirus Task Force response coordinator Dr. Deborah Birx has specifically advised governors in Indiana, Ohio and Kentucky to limit bars and restaurants from opening as cases surge.

All this while the virus continues to hit close to the Oval Office, with the announcement Monday that national security adviser Robert O'Brien had become the highest-ranking U.S. official known to have tested positive for COVID-19.

Of course, ironically for the president, one of the fastest ways to restart the economy would be to dramatically expand testing and limit the wait times for results. While testing capabilities in the U.S. have improved, if more asymptotic Americans could readily get timely tests, more would likely feel comfortable traveling, working and spending money.

The TIP with Averi Harper

As the mostly virtual Democratic National Convention nears and former Vice President Joe Biden's pick for running mate looms, progressives are attempting to leverage their influence to push the Democratic Party toward progressive ideals.

In Monday's hours-long virtual Democratic National Committee Platform Meeting, the divide between the moderate and liberal ends of the party was apparent, with progressives on the losing end of many amendment discussions. In a Zoom call with delegates last week, Sen. Bernie Sanders encouraged his more than 1,000 delegates to "engage in coalition politics with a goal of defeating Trump" and to "make sure that a Biden administration is the most progressive administration in modern American history."

Progressive groups Roots Action, Progressive Democrats for America and Our Revolution issued a joint statement claiming Sens. Kamala Harris, Tammy Duckworth and Rep. Val Demings would be the "wrong choice for vice president," citing that they didn't support a congressional amendment to reduce the Pentagon's budget. The statement referred to Sens. Elizabeth Warren, Tammy Baldwin and Rep. Karen Bass as favorable choices.

DNC Chair Tom Perez downplayed differences between the factions during a committee meeting, saying, "We should never confuse unity with unanimity, nor should we confuse debate with division."

ONE MORE THING

As the COVID-19 pandemic surges within the United States, the Trump administration’s task force leading federal efforts to slow the spread of the virus continues to relay some optimistic messages in its meetings. But -- during an in-depth interview that will air Tuesday night on ABC News as part of a primetime special, “American Catastrophe: How Did We Get Here?" -- Dr. Anthony Fauci, a key member of the task force as the nation’s top infectious disease expert, said those claims do not always match the reports he receives from the front lines of the crisis.

THE PLAYLIST

ABC News' "Start Here" podcast. Tuesday morning's episode features ABC News' Trish Turner, who tells us exactly what's in the GOP proposal for the next coronavirus relief package. Then, Jessica Mendoza from our partners at ESPN explains why the COVID-19 outbreak within the Miami Marlins locker room could spell trouble for the rest of the league. And, ABC News Senior White House correspondent Cecilia Vega previews the 20/20 special "American Catastrophe: How Did We Get Here," which traces where the U.S. coronavirus response went wrong. http://apple.co/2HPocUL

WHAT YOU NEED TO KNOW TODAY