Is anyone really worried about a situation where a president commits a crime and then voluntarily resigns? Authoritarians only do the first half...

That has literally happened in the United States before.

Trump has already proven himself to be more corrupt and sociopathic than Nixon. He was impeached and convicted and didn't resign. He is now a convicted felon and continues to pursue a second term. This is a different world.

Trump was not convicted at the impeachment trials.

https://en.wikipedia.org/wiki/First_impeachment_trial_of_Don...

https://en.wikipedia.org/wiki/Second_impeachment_trial_of_Do...

He was impeached, and every single politician voted on party line, the whole GOP is 100% corrupt (if you agree he clearly did do it) impeachment is not a useful tool in this situation.

From the Wikipedia page linked above:

> Seven Republican senators joined all Democratic and independent senators in voting to convict Trump, the largest bipartisan vote for an impeachment conviction of a U.S. president or former U.S. president. After the vote on the acquittal, Mitch McConnell said, "There's no question that President Trump is practically and morally responsible for provoking the events of the day." but he voted against conviction due to his interpretation of the United States Constitution.

It's worth noting that the Supreme Court ruling here probably disagrees with McConnell's interpretation of the Constitution in a way that should have changed his vote.

Yes, I'm aware, but it's also not what I'm worried about. And I doubt it's what anyone who is alarmed by this ruling is worried about. I dream of a world where the biggest concern we have is a president doing something illegal and then giving up the most powerful office in the land to avoid consequences. Does anyone think that Nixon would have resigned if this happened in 2024?

Nixon resigned because he was going to be impeached, and convicted in the impeachment, and he couldn't stop it. The House committee (whichever one originates such things) had already voted to impeach. It was then going to go to the full House, which would have voted to impeach, but Nixon resigned first.

To show what a different world it was then, the chair of the House committee, a Democrat, called his wife to tell her "we voted to impeach", *and then started crying" because it was horrible that it had come to that, and that the president had done such things. Today they would have been cheering.

The military doesn't let you "resign," and former service members can be charged in civilian federal court.

Not necessarily. SILTs and RILTs are options for case disposition, but the accused does not have the power to execute one unilaterally. It's a form of plea deal, usually for military-specific offenses.