The US has largest defense budget by far, and .01% would be less than $100 million, right? Could you really create enough mining capacity for that to take over

The US has largest defense budget by far, and .01% would be less than $100 million, right? Could you really create enough mining capacity for that to take over the network? Better question: by the time Bitcoin gets to the point that a government feels threatened enough to do this, will they be able to? And how will other governments respond? Will they start mining too so that no one government controls the network?