Flip in that Congress won’t be able to support their favorite Iran partner. Flip in that he will veto horrible budgets instead of pushing for them, push for military, etc.
Just as a point of information, because I’m sure you meant “appropriations” when you said “budget” (the two are erroneously used interchangeably), the Budget is passed as a resolution, not as a law. Therefore the President has no veto power.
Again, I know what you meant, but want to make sure lurking FReepers understand as well.