The forced resignation of Homeland Security Secretary Kirstjen Nielsen is being widely described as the beginning of President Trump's purge of Homeland Security Department leadership. Trump can't legally replace Nielsen with his handpicked interim successor, Customs and Border Protection Commissioner Kevin McAleenan, as long as the last of the DHS's top leadership, Claire Grady, remains in the line of succession, so White House officials are pushing Grady to resign before Nielsen officially steps down on Wednesday, The Wall Street Journal reports.

Trump's also rumored to be on the verge of dismissing U.S. Citizenship and Immigration Services head Lee Francis Cissna, USCIS policy chief Kathy Nuebel Kovarik, and DHS general counsel John Mitnick. In a memo about his own ouster Monday, Secret Service Director Randolph "Tex" Alles told his staff Trump warned him weeks ago that "transitions in leadership should be expected across the Department of Homeland Security," the Journal reports. Trump also "recently told Stephen Miller, one of his most hard-line advisers: 'You're in charge' of the administration's immigration policy," the Journal adds, citing an administration official.

"Trump's congressional allies are alarmed by his purge at the Department of Homeland Security — urging him not to fire more top officials," Politico reports. No Republican is being more vocal than Sen. Charles Grassley (R-Iowa). In an unusual move, Grassley told The Washington Post late Monday he's "very, very concerned" about Cissna's fate, particularly.

The people targeted by Trump "are the intellectual basis for what the president wants to accomplish in immigration," Grassley told the Post. "He's pulling the rug out from the very people that are trying to help him accomplish his goal." Grassley also took a jab at Miller, saying "I think it would be hard for him to demonstrate he's accomplished anything for the president." Asked to elaborate, Grassley chuckled: "It's pretty hard to elaborate on it when there hasn't been any accomplishments." Peter Weber

After much speculation, President Trump's defense team finally reeled the Biden family into the Senate impeachment trial Monday.

For the most part, the case against impeachment was focused on poking holes in the Democrats' opposing argument, but former Florida Attorney General Pam Bondi, who's defending the president, made former Vice President Joe Biden, his son Hunter, and Burisma — the Ukrainian gas company upon whose board Hunter Biden sat — the centerpieces of her presentation, as did another Trump attorney Eric Herschmann.

Their point was that Burisma's corruption made Trump's investigation request legitimate, and since the Bidens were connected to the company, they were worth looking into, as well. Bondi described the younger Biden's board membership as "nepotistic at best, nefarious at worst."

A few people sensed some hypocrisy in those comments, implying that Trump supporters don't have much ground to stand on when it comes to nepotism accusations.

There were a few other challenges to Bondi's argument, including the idea that, even if Hunter Biden's activities were corrupt, there are other ways to investigate foreign corruption than the Trump administration's methods in this case. Tim O'Donnell

Stop us if you've heard this one: an awards show just slipped in the ratings and drew its smallest audience in years.

This time, it's the 2020 Grammy Awards, which 18.7 million viewers tuned into on Sunday night, per The Hollywood Reporter. That's the Grammys' smallest audience since 2008, when 17.18 million viewers tuned in, the Reporter notes. The 2006 Grammys remain the show's all-time low in terms of viewership, as 17 million people watched that year.

The 2020 Grammys also drew a 5.4 rating among adults 18-49, which Variety notes makes it the lowest-rated, if not the least-watched, Grammys ever.

Still, TVLine notes that this year's Grammys, which saw Billie Eilish sweep the four top categories, was the TV season's highest-rated entertainment program so far. But this continues the trend of awards shows slipping in the ratings after the 2020 Golden Globes drew the smallest audience in eight years. Before that, the 2019 Emmys was a ratings catastrophe, drawing the smallest audience in Emmys history and plunging more than 30 percent from the previous year. With that in mind, the Grammys' drop certainly could have been worse seeing as the Reporter notes the show only declined about five percent in viewers.

Some awards shows have bucked this downward trend, though, including the 2019 Academy Awards, which actually improved its viewership after years of declines. Can the 2020 Oscars hold steady, or will it once again slip like the Grammys? We'll find out when the Oscars air, once again without a host, on Feb. 9. Brendan Morrow

Sen. Amy Klobuchar might prove to be the most important Democratic presidential candidate when all is said and done in Iowa next week — even if she doesn't win the state's caucus.

That's because many Iowa voters appear to be split among moderate candidates like Klobuchar, South Bend, Indiana, Mayor Pete Buttigieg, and former Vice President Joe Biden, which The New York Times reports is at least playing a role in the rise of Sen. Bernie Sanders (I-Vt.). If those moderate voters want to prevent Sanders from getting a head start toward the nomination with an Iowa victory, per The Times, rallying around one of the other candidates seems like a good place to start.

Klobuchar is doing pretty well in Iowa, but she's lagging behind Buttigieg and Biden, so her supporters are seen as having the most potential to make a switch, especially because of the caucus' multiphase process. If Klobuchar struggles to pick up the votes she needs early on, those backing her could theoretically shift to a stronger candidate and help push someone like Biden to victory.

It sounds like some in the Biden camp are aware of this. Former Iowa Gov. Tom Vilsack, who's thrown his weight behind the Biden campaign, thinks Biden can appeal to Klobuchar's crowd since both politicians frame themselves as pragmatists, and well, as he puts it, "Joe is going to need a running mate." Read more at The New York Times. Tim O'Donnell

This might be the most easily debunked claim of the whole impeachment trial.

President Trump's team of defenders got their turn on the Senate floor on Monday, with one of them, Trump lawyer Jane Raskin, employing a new strategy to distance Trump from his lawyer and Ukraine link Rudy Giuliani altogether. "In this trial, in this moment, Mr. Giuliani is just a minor player, that shiny object designed to distract you," Raskin said. "Senators, I urge you most respectfully, do not be distracted."

While Raskin may try to downplay Giuliani's involvement, the transcript of Trump's July phone call with Ukrainian President Volodymyr Zelensky, which Trump so often begs the world to read, would say otherwise. Giuliani's name comes up no less than six times in that call memo, with Trump mentioning "Giuliani" two times and "Rudy" twice as well.

There are also all those times impeachment witnesses told the House that Giuliani was deeply tied to Trump's Ukraine dealings, with a few of them explicitly saying how Trump had told them to "talk to Rudy" when they had concerns about the country. Oh, and don't forget all those other times Giuliani himself talked up his involvement with Ukraine while making gaffe after gaffe on national TV. Kathryn Krawczyk

Fox News' Chris Wallace is once again calling out pro-Trump spin on the network, even slamming one contributor on air in a tense exchange.

Wallace spoke Monday about the explosive New York Times report that former National Security Adviser John Bolton in his upcoming book writes that President Trump told him he wanted to continue withholding aid to Ukraine until officials helped with investigations into former Vice President Joe Biden and his son.

To get a sense of how "big" this news is, one only has to look at Trump supporters "spinning like crazy that it isn't big news," said Wallace. This only reinforces that this is a "really important development in this case," he continued, per Mediaite.

Wallace went on to observe that it's now "much, much less likely" that Trump's impeachment trial will wrap up on Friday without any witnesses being called, as the Bolton news makes it "awfully hard" for Republican senators on the fence about calling witnesses to vote against doing so.

Not long after, Wallace got into an argument with contributor Katie Pavlich about the idea of calling Bolton to testify after she claimed that in "every impeachment beforehand, the witnesses that were called had been called in the House before being brought to the Senate."

"In the Clinton impeachment, they'd been called by the independent counsel," Wallace told her, adding, "Get your facts straight!" Brendan Morrow

The Senate would probably want to hear from a firsthand witness in President Trump's impeachment trial. But Sen. Josh Hawley (R-Mo.) isn't sure where you'd find one.

Despite a Sunday report indicating former National Security Adviser John Bolton will say in his book he spoke directly to President Trump about Ukraine, a number of GOP senators still don't want to hear from him in Trump's impeachment trial. Hawley is among those lawmakers, giving new reasoning to his anti-Bolton argument Monday by questioning whether Bolton even was a firsthand witness to Trump's alleged crimes.

Bolton's book reportedly describes how Trump talked to his former adviser about withholding security assistance from Ukraine until it agreed to investigate former Vice President Joe Biden. And with Republicans largely complaining impeachment witnesses testified to the House based on "hearsay," one would think they'd like to hear from someone who was actually in, as Bolton's book title so aptly puts it, "the room where it happened." Kathryn Krawczyk