OC, remember, the Pres can only suggest and guide legislation, it is up to congress to enact the laws and the supremes to interpret them. This is the "Checks and Balances" that you speak of.
That said, over the years, the executive branch has worked and watered down the interpretation of constitution through executive order to eliminate Checks and Balance on the thing that could have the greatest effect on this nation-going to war. And this primarily under the "constitutional constructionist" watchful eyes of Reinquist and Scalia. (But that's another topic.I feel a rant coming on)
So when you have an egomaniacal mental light weight bent on revenge (for daddy) and securing more wealth for the members of his club, surrounded by equally twisted yes-men, you get ... well ... WAR.
Oops, did I say that?