"As an American citizen" - buddy we are not known for our intelligence or our honor so I don't know what relevance you think that has.
And yes there is such a thing as bad press before an election. That's why politicians go to huge lengthsto bury stories before elections.
Speaking as an American citizen, that cracks me up.
What do you think are going to be the actual repercussions, in the US, of learning that the US president is trying to secure exclusive US control of a vaccine for COVID19 for priority distribution in the US?
They aren't going to be any. Indeed, to his base, stuff like this is exactly why they voted for him. (If Trump had succeeded in securing that vaccine solely for the US, he would win in November in a landslide.) And that's pretty much the extent of the calculations that went on in his head when he attempted this stunt.
It's a good thing he failed. But let's be responsible about disclosure and time it so that he can't derive any political benefit from it.
[edit: too many "any"]