The indictment of former Trump campaign chair Paul Manafort sets the stage for a historic test of the American legal and political systems, which could soon come under new attack from a president who has previously asked his advisers about firing Special Counsel Robert Mueller and pardoning those caught up in the Russia probe.
Mueller's painstakingly detailed 31-page indictment of Manafort and former Trump campaign aide Rick Gates alleges that the two men concealed their ties to the government of Ukraine, kept huge amounts of money in offshore shelters, and laundered more than $18 million since 2006.
The indictment doesn't allege that they colluded with Moscow to help Trump win the 2016 election, which the president and his aides are already using to try to undermine Mueller and dismiss the ongoing probes into team Trump's ties to Russia as partisan witch hunts.
But the key thing to understand about the indictments — and the guilty plea of a lesser-known Trump adviser named George Papadopoulos — isn't about their possible impact on the current course of the Trump-Russia scandal. It's about their probable impact on what's still to come.
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That's because Mueller's moves increase the likelihood that campaign advisers or administration staffers who find themselves in the special counsel's crosshairs may look to strike plea bargains where they swap damaging information on Trump in exchange for lesser charges. Papadopoulos is already cooperating with the Mueller team.
As a result, Trump may decide that he has no choice but to try to protect himself by firing Mueller or issuing preemptive pardons to Manafort or others ensnared in the investigation.
Either move would trigger a political and legal crisis on a scale that hasn't been seen since Watergate, with federal courts having to decide whether to overturn any of the Trump pardons and Republicans facing a moment of truth about their willingness to substantively stand up to Trump instead of merely criticizing him publicly.
The investigation into Trump's ties to Russia has been simmering along for months, and it wasn't clear if, or when, it would move from a political scandal to a legal one. With Monday's moves by the Mueller team, it has. The question is how far Trump is willing to go to protect himself from an investigation that threatens the future of his presidency — and whether Congress and the courts are up to the challenge.