Normally I'd be very skeptical of an article like this one. According to the article, President Bush was mulling the political benefits of invading Iraq as long ago as 1999:

"Exclusive: Bush Wanted To Invade Iraq If Elected in 2000."

“He was thinking about invading Iraq in 1999,” said author and journalist Mickey Herskowitz. “It was on his mind. He said to me: ‘One of the keys to being seen as a great leader is to be seen as a commander-in-chief.’ And he said, ‘My father had all this political capital built up when he drove the Iraqis out of Kuwait and he wasted it.’ He said, ‘If I have a chance to invade….if I had that much capital, I’m not going to waste it. I’m going to get everything passed that I want to get passed and I’m going to have a successful presidency.”