How about enhanced airport security? Maybe profile Arab men a bit?
To say he could have done nothing is ludicrous.
You do realize that the various security agencies are constantly churning out reports, studies, etc. coming up with possible ways our enemies might attack us with. I'm sure presidents also get reports on countries like North Korea and their nuke capabilities, and all sorts of threats all over the world.
In any given week there are probably also several threats to the president himself that the Secret Service has to follow up on on to make sure they're not credible threats.
Pay me a handsome salary and put me in an office and I too will churn out reports on a daily basis listing all sorts of creative things the terrorists might someday come up with.
I blame 9-11 on the terrorists first, and if there's secondary blame it goes to Clinton for all his work in screwing up our different agencies' ability to communicate with each other efficiently.
Honestly, if GWB were to act on every desk jockey's reports on terrorist opportunity then there would be no public transport, no public buildings, everyone would be under constant house arrest. Every dam and water reservoir would require a small army to guard it, every road would have checkpoints where citizens would undergo searches all the time.
Hindsight is 20/20. I hereby predict that someday a terrorist will attempt to bomb a football stadium. Should the government now disallow the use of football stadiums indefinitely just in case?