I don't think that's right – the US President can pardon someone for a federal crime which they haven't even been charged with yet. Ford pardoned Nixon even though he hadn't been charged with any federal crime, and that was sufficient to bar any future federal prosecution of Nixon for the crimes to which the pardon applied.

However, from what I understand, the state charge is not that he violated federal election laws, but rather he committed the state crime with the intention of violating federal election laws. So, they don't need to prove he actually committed a federal crime, only that he committed a state crime with the intention of committing a federal crime, even if he never actually committed the federal crime which (they allege) he was intending to commit. Which is probably why any federal pardon would be legally irrelevant. However, it likely does give the federal courts greater grounds on which to hear an appeal than they normally would in a state criminal case – if a state court concludes that Trump intended to do X, and that X is a federal crime, federal appellate courts could always rule that X is not a federal crime (whether or not Trump did it), thereby destroying the legal theory behind the state conviction.

> However it does raise the question: Is it proper to convict someone of a state crime based on “criminality” where the criminality is a federal crime that they have not been convicted of in federal court? It seems unlikely.

Personally, I think people are going to look back on this as a big mistake on Alvin Bragg's part – charging Trump on what appears to be a highly technical and complex legal theory, for acts which in themselves were on the low end of criminal severity. Trump is likely to beat this one way or another, which will help his narrative of "I'm being persecuted by left-wing prosecutors".

If you believe Trump is guilty of far worse offences (such as trying to overturn the result of a democratic election), you don't want to see that narrative being given legs, since it may make it harder for prosecutors to win if they bring those more serious charges. It is even possible that this might lead to the Republican party uniting behind Trump and guaranteeing him the nomination–what happens if Trump wins in 2024 (whether fairly or unfairly)? Future historians may come to see this as a key event in helping make that happen. In hindsight, people might come to see Alvin Bragg as having unintentionally done Trump a big favour.

> In any case, I believe all of this is just media speculation and presumably there will be more clear-cut charges in the real indictment.

My impression this is not mere "speculation", rather leaks coming from insiders who know what is in the sealed indictment, making it more likely to be true – but of course, with any leaks, there is always the chance they are inaccurate in some way. We'll see.