"You mispoke on that issue? No grant. You were of the wrong political perssuassion? No grant. Hurt the feelings of X group? No grant."
Are you talking about not getting the grant in the first place, or are you talking about grants being cancelled after they had been approved and you had taken the money and started doing the funded work?
Those two situations are different.
They are different situations, but both are equally applicable here. 1. Grants can be canceled at will. 2. All grants are approved or denied by political appointees, who are instructed to only treat peer review as advisory considerations.