America was attacked on 9/11, which meets the War Powers Act criteria investing him as Commander in Chief in combating terrorism.
The power to detain American citizens as "enemy combatants" without benefit of a judge or specific Congressional authorization was a stretch on the President's part, in that the conflict did not meet the classical definition of a "war" in that no opposing nation could be identified. That left things more open-ended than they should have been. I really don't want to see that kind of power in the national government in this country.
As to the war in Iraq, Congress authorized military action. So in both these instances, President Bush exhibited at least some respect for both Statutory and Constitutional restrictions of his powers as President.
By contrast, the action in Libya is totally illegal. This leftist author just can't bring himself to admit it, needing the cover of parity to somehow portray himself as 'even-handed' in the eyes of his blatantly partisan readership.
Sure, he is partisan, but all people are.
Bush was brought up in the article to prove the point that Obama is basing his decisions under the status that he is the sole principle in deciding military action, as per Bush.
As for the Constitutional mertis of Iraq. Authorization of force, is not a product or use in the Constitution. Congress can declare War, that's it.
Excellent summary and reminder!