President Trump is considering declaring a national emergency over his proposed border wall, but some Republicans are fearful over what a future Democratic president could do with that power.

Conservative commentator Erick Erickson is among those who think Trump shouldn't take this route because of the precedent it would establish. "When the next Democratic President declares a national emergency over gun violence and takes executive actions to curtail gun purchases, you can thank the people urging Donald Trump to do the same with regards to the border," he wrote on Twitter. Fox News' Brian Kilmeade, too, issued this warning Thursday, suggesting an emergency could be declared over climate change in a Democratic administration.

This sentiment has not only been popular among conservative pundits, though, with Sen. Marco Rubio (R-Fl.) telling CNBC, "If today, the national emergency is border security ... tomorrow the national emergency might be climate change." Rep. Matt Gaetz (R-Fl.), meanwhile, has a different worry: that the next Democrat could use their emergency powers to say "we have to build transgender bathrooms in every elementary school in America," Talking Points Memo reports. Others have been offering more general warnings, as Vox points out, with Sen. Chuck Grassley (R-Iowa) agreeing that Trump's declaration would be a "bad precedent" in an interview with CNBC.

Sen. Bernie Sanders (I-Vt.) seemed to prove some of these fears valid in a Friday tweet, listing a number of non-wall issues he considers national emergencies, including gun violence and climate change.

One Republican who clearly has no concern about this is Sen. Lindsey Graham (R-S.C.), who, after unsuccessfully attempting to broker an agreement with his fellow members of Congress, urged Trump to "Declare emergency, build the wall now." To that, conservative columnist Jonah Goldberg replied, "Can't wait to see what the next Dem president does with that precedent, Lindsey." Brendan Morrow

Former Special Counsel Robert Mueller won't testify before two House committees until Wednesday morning, but the pregame show has already started on cable news. CNN's Anderson Cooper deconstructed President Trump's lies about Mueller and then had a panel of experts, including former White House counsel and Watergate star witness John Dean, preview Mueller's testimony. Dean argued that if Mueller had been the Watergate prosecutor, Richard Nixon would have gotten away with his alleged crimes.

On MSNBC, Ari Melber pointed to reports that Attorney General William Barr "is stepping in again" and trying to limit what Mueller says. And Mueller will not be "standing with the president's critics," he added. "Remember, as a legal matter, when Mueller steps in front of the world Wednesday, he will be a hostile witness under subpoena. He is prepping to be pressed and to push back."

"There are damning facts in the Mueller report, but some Democrats want more than a dry, factual presentation," Melber said. "They want to press Bob Mueller under oath to say in English what the Mueller report only said in lawyer jargon: That there is substantial evidence against Trump, that it comes from his own staff, and that it suggests he committed multiple crimes in office."

Former Solicitor General Neal Katyal told Melber he's "extremely concerned" about the reports Barr is, in his analysis, "trying to gag Mueller and trying to say that anything that's not in the report is 'presumptively privileged.' And you know, Mueller is so by-the-book, I suspect that will influence him greatly, what Barr and others are trying to say in terms of squelching him." At the same time, Mueller's "by-the-book" nature could also work against Trump, Katyal suggested, because "the book's actually changed" since Mueller turned in his report, specifically because Barr has since said he could have reached a conclusion about whether Trump has committed crimes.

Whether Mueller would have said Trump committed crimes is "exactly the kind of question the Democrats should be leading the hearing with," Katyal said. Melber said Katyal was engaging in "a little bit of wishful thinking," but Katyal said given Barr's comments, Mueller "absolutely should go further" than what's in his report, "and indeed I don't see how he can't answer that question." Peter Weber

Whenever there's a big scandal unfolding, President Trump works to distract everyone, causing a commotion so no one can remember the original impropriety, Seth Meyers said on Monday's Late Night.

That's likely one reason why he can't stop talking and tweeting about "The Squad," the four Democratic congresswomen of color he's been attacking for more than a week now. Over the weekend and on Monday, Trump said the lawmakers are not capable of "loving" the United States, and called them, among other things, "racist" and "not very smart." So, why the big distraction? It involves Special Counsel Robert Mueller, Meyers said.

Mueller is scheduled to testify in front of two congressional committees on Wednesday, answering questions about his investigation into Russian meddling in the 2016 presidential election and obstruction of justice. (Trump scheduled his North Carolina rally last week on the day Mueller was originally set to testify.) Mueller will most likely be asked about the Justice Department memo that states a president cannot be indicted while sitting in office, and whether Trump would have been indicted had it not been for those guidelines — something Meyers finds bonkers. "That's right, Trump can't be indicted because of a memo written in 1973," he said. "People ignore memos every day. We sent out 15 memos, yet Devon is still microwaving fish in the break room."

On top of the Mueller testimony, court documents unsealed last week in Michael Cohen's case show the president knew Cohen was making hush payments to adult film star Stormy Daniels, who said she had an affair with Trump. That development "wasn't even in the Top 10 news stories last week," Meyers said. "This is how he wears us down. It's like being in a zombie movie — anybody can outrun one zombie, but when your city is crawling with zombies, you're like f--k it, just eat me." Watch the video below. Catherine Garcia

To President Trump, Stephen Miller is a senior policy adviser. To David Glosser, he's his "immigration hypocrite" of a nephew.

Last August, Glosser, a retired neuropsychologist, penned an essay about Miller, the architect of Trump's harsh immigration policies. Glosser wrote that their relatives came to the U.S. in the early 1900s from Europe, fleeing anti-Jewish violence, and he shuddered to think "of what would have become of the Glossers had the same policies Stephen so coolly espouses" been in effect.

His message didn't get through to Miller, Glosser said on Monday's Rachel Maddow Show, but he didn't think it would, as Miller's "entire career, his entire persona, is built on this particular issue." Glosser did hear from others whose families came to the U.S. under similar circumstances, he said, and seeing Americans speaking out against the Trump administration's treatment of immigrants shows that "people care, as it turns out."

The political reasoning behind Trump's cruel policies is simple, Glosser said. The Republican Party and demographers found that in a few decades, the U.S. will go from being a "white majority country to being a white plurality country. As it turns out, the people who are not predominately of European background are less likely to vote for Republicans than for Democrats. This makes it problematic for them if they anticipate remaining in positions of power in order to advance their particular agenda." Because of this, he said, it's "not worthwhile for them to allow people into the country or to allow people to gain citizenship who may not be members of their party in the future."

Glosser said he finds it "repugnant" that the Trump administration assumes a majority of white Americans are racist, and thought the country had repudiated racism since George Wallace's 1968 presidential run. "Now we see Mr. Trump and his minions have legitimized race hatred as a means of sustaining and gaining political power and influence," he said. Catherine Garcia

Since June 7, migrant flow through Mexico has dropped by 36.2 percent, the country's foreign minister told reporters on Monday.

Marcelo Ebrard credits the Mexican government's decision to deploy 20,000 members of a new militarized police force to the country's southern border. The plan went into action after President Trump threatened Mexico with tariffs if it didn't slow down the flow of migrants making their way to the U.S. border.

The National Immigration Institute states that during the week of June 1 to 7, an average of 4,156 migrants entered Mexico daily through its southern border. Two weeks later, this number declined to 2,652 people per day, The Guardian reports. After making their deal in June, the U.S. and Mexico agreed to reconvene after 45 days to come up with new target numbers, but until then, "we're going to keep up this effort so the trend continues downward," Ebrard said. Catherine Garcia

The White House and congressional leaders have reached a two-year budget deal that would raise spending caps by $320 billion and suspend the debt ceiling, President Trump announced on Twitter Monday evening.

"This was a real compromise to give another big victory to our Great Military and Vets!" he added. Congress still has to pass the deal, which would set spending levels through Sept. 30, 2022 and suspend the debt ceiling until July 31, 2021. The agreement was brokered between House Speaker Nancy Pelosi (D-Calif.) and Treasury Secretary Steven Mnuchin.

Some Democrats and Republicans have voiced their displeasure with the deal, including Sen. Patrick Leahy (D-Vt.), who is angry it does not keep Trump from using funds to build his wall along the southern border, and Rep. Mike Johnson (R-La.), who is outraged the agreement adds to the country's debt. The debt has grown from about $19 trillion in January 2017 to more than $22 trillion now, but speaking to reporters on Monday, Trump said he thinks the U.S. is "doing very well on debt, if you look at debt limit, however you want to define that, but we're doing very well on that and I think we're doing pretty well on a budget." Catherine Garcia

When Vice President Mike Pence's trip to New Hampshire was canceled earlier this month at literally the last minute, the reason shrouded in secrecy, people started talking — what could possibly have happened to keep Air Force Two from leaving D.C.?

Pence was set to visit a Granite Recovery Center to meet with former patients and talk about the opioid epidemic, but instead, he got off the plane and went to the White House. Trump promised reporters the reason would be revealed "in about two weeks," and on Monday, law enforcement officials told Politico the trip was called off because Pence would have likely met a person being investigated by the Drug Enforcement Administration for moving more than $100,000 of fentanyl from Massachusetts to New Hampshire.

The man, former New York Giants player Jeff Hatch, worked for Granite Recovery Centers. He appeared in federal court on Friday and agreed to plead guilty to a single count of using a telephone to help commit a crime, court records show; he faces four years in prison. Hatch toured New Hampshire and spoke to young people about the dangers of drug use, often sharing a stage with Sen. Jeanne Shaheen (D-N.H.). In a statement, Shaheen said people "seeking recovery from substance use disorders put their trust in Mr. Hatch and it's incredibly disappointing to see how badly that trust was betrayed. He needs to be held accountable." Catherine Garcia