The US is and has been, uh ...safer, from a major terrorist attack since 9/12. It's the jack-in-the-box principle, now indulge me here: a 2 year old dies from eating a Jack in the Box hamburger made from beef tainted with E-coli bacteria in 1993. It's a huge national news story, and most everyone is afraid to eat at Jack in the Box for months afterwards. I said then that Jack in the Box hamburgers were the safest hamburgers, because Jack in the Box wants to stay in business.
After the insane video spectacle of 9-11, committing a successful terrorist attack in the US became MUCH more difficult. And after 9-11 it wasn't just the Government that was hyper-alert, it was everyone in the country.
Today we are likely less safe than the first few years after 9-11, but it isn't just because we have made more angry terrorists. It's because our level of alertness goes down as time passes since Sept. 11, 2001.
We had our pants down at the end of the halcyon days of the tech-booming Clinton years, plain and simple. When most Americans are relatively content, we are less afraid and stressed- our kids are listening to shittier music and we are statistically less safe from terrorist attacks.