I'm not sure what David Crosby means by his statement that President Bush should be held "personally accountable" for prisoner abuse at Abu Ghraib prison. If Mr. Crosby means that the president should be voted out of office, it's a reasonable position whether or not you agree with it. Usually, though, one who is "personally accountable" for illegal acts pays a fine or goes to jail. If we are to hold our presidents accountable in this sense, we may have trouble attracting quality candidates because, as Mr. Crosby notes, atrocities are inevitable in war, and even Dennis Kucinich recognizes the legitimacy of war as a last resort.
For anyone interested in the doctrine of preemptive war, I recommend "Surprise, Security, and the American Experience" by John Gaddis (Harvard University Press, 2004). This book makes it clear that George W. Bush has not, as Mr. Crosby contends, broken tradition with two centuries of American foreign policy. Instead, he has returned to a policy of pre-emptive strikes first adopted by John Adams in reaction to the British sack of Washington D.C. in 1814, then extended to establishing our borders after the collapse of Spain's colonial empire, especially in Florida. James K. Polk did much the same thing in Texas. This adventurous unilateralism dominated our foreign policy until Franklin Roosevelt recognized the utility of letting other people start wars that the United States could finish, thereby creating hegemony by consent. You may not agree with the Bush administration's rejection of multilateralism, but it's a return to, not a break from, traditional American foreign policy.