The federal budget is significantly more than 1 Trillion USD
Anyway, the fraction of the budget is really besides the point. We spend an inordinate amount of money on the military, and there is no viable threats to defend against. China is the best pick because they spend the second most money ($85 billion), but can we legitimately think that we'll go to physical war with such a huge trade partner?
Our military is funded by campfire stories and yellow press.