If President Trump wanted to fire special counsel Robert Mueller, he would have had to do it before Tuesday.

Of course, there's never been a good time for Trump to fire Mueller, and whether it happened before this week or not, it would have been a problem for the president. But until Tuesday, he perhaps could have gotten away with it.

After more than a year, special counsel fatigue seemed ascendant, and there was a good argument to be made that Mueller's (public) findings weren't living up to the #Resistance's hype about collusion. It was easier to see how Trump's complaints of a "witch hunt" would be persuasive to voters.

[Related: If Trump fires Mueller, Democrats have plan to protect documents, special counsel personnel: Report]

But the guilty verdicts against his former campaign manager Paul Manafort, and the guilty pleas from his former personal attorney Michael Cohen — both of which came down within minutes of each other on Tuesday evening — changed that.

No, they had nothing to do with collusion between Trump and the Russian government. But they demonstrated more definitively to the public there were serious problems of corruption in Trump's orbit. And Cohen implicated Trump in a campaign finance violation, which sounds dry until you consider the allegation involves possibly skirting the law to pay off women accusing Trump of having affairs with them. To many voters outside the pro and anti-Trump trenches, people who were growing frustrated with the Russia probe but aren't fiercely loyal or opposed to the president, Tuesday probably granted Mueller's efforts more legitimacy.

None of this is to say Trump couldn't still win re-election, or that he'll be impeached. But if he moves to fire Mueller at this point, it would probably be acceptable only to his base, incurring political consequences beyond survivability. I'm not sure that would have been true before Tuesday.