5031 US citizen deaths caused by terrorism in 148 years is 34 per year.

US citizen deaths caused by terrorism in 2011: 17 [1]

So no, it doesn't seem to have spiked apart from obvious outliers like 9/11.

[1] http://www.state.gov/j/ct/rls/crt/2011/195556.htm

If you only look at the US, maybe just the one spike on that well known date.

If you look at the entire Western world as a whole, my guess is that deadly terrorism on the whole has actually decreased pretty dramatically since the 80's.