I agree with the posts above, but would like to make this point for the sake of conversation and in the interest of nit-picking. The US has acted reasonably to maintain civil liberties in the context of its war on terrorism but could have done better.
When compared to a liberal ideal, the administrations of the 2000s have done a good job to increase international and national security while largely avoiding impingements upon individual privacy and freedom (at least it seems that way to me), yet some of the legal maneuvers in this period have seemed unnecessary for security and detrimental to liberty. (I think here of airport security and Guantanamo Bay Prison.)
So, if this were a yes or no question, I'd respond with a yes, but a qualified yes.