The report that former national security adviser John Bolton’s book says Donald Trump told him that nearly $400 million in military aid to Ukraine was held up to pressure the country to interfere in the 2020 elections is a direct challenge to every Republican senator. The supposedly “moderate” Republican senators have been frantically searching for any excuse to vote against calling witnesses in Trump’s impeachment—Democrats were mean! Why didn’t the House spend months and months in the courts so that Republicans could accuse them of impeaching close to an election?—but with a report that one of the key witnesses Democrats are seeking can and will fill in exactly what Trump said about his pressure campaign against Ukraine, their excuses are all gone.

That’s not to say that Sens. Susan Collins, Lisa Murkowski, Cory Gardner, Mitt Romney, and Lamar Alexander will do the right thing. Four of them need to step up and vote for a real trial rather than a continued cover-up. Four of them—or any other Senate Republican—need to be brave enough to go against Trump and Senate Majority Leader Mitch McConnell. But the fact that we have to question whether four out of 53 Republicans will do this most basic thing to protect the integrity of the presidency and U.S. democracy is yet another indictment of today’s Republican Party and its drive for power above all else.

John Bolton is a hard-right warmonger, but somehow Senate Republicans and Donald Trump are making him look good—that’s how bad they are. “Bolton's motivations for testimony - he has a story he wants to tell, and he is concerned he'll be accused of holding stuff back to juice his book sales instead of speaking out,” New York Times reporter Maggie Haberman tweeted.

Now it’s on the Senate. Specifically, any four Senate Republicans to say that they put country, Constitution, and democracy above the short-term interests of Donald Trump and his Republican Party.