It seems that that White House’s top lawyer seemed to think it was a possibility and raised the issue two years ago.
MSNBC - Memos Reveal War Crimes Warnings
The concern about possible future prosecution for war crimes—and that it might even apply to Bush administration officials themselves—is contained in a crucial portion of an internal January 25, 2002, memo by White House counsel Alberto Gonzales obtained by NEWSWEEK. It urges President George Bush declare the war in Afghanistan, including the detention of Taliban and Al Qaeda fighters, exempt from the provisions of the Geneva Convention.
In the memo, the White House lawyer focused on a little known 1996 law passed by Congress, known as the War Crimes Act, that banned any Americans from committing war crimes—defined in part as “grave breaches” of the Geneva Conventions. Noting that the law applies to “U.S. officials” and that punishments for violators “include the death penalty,” Gonzales told Bush that “it was difficult to predict with confidence” how Justice Department prosecutors might apply the law in the future. This was especially the case given that some of the language in the Geneva Conventions—such as that outlawing “outrages upon personal dignity” and “inhuman treatment” of prisoners—was “undefined.”
It’s somewhat interesting to note that Gonzales specifically mentioned the GPW’s rules regarding “outrages upon personal dignity” and “inhuman treatment” as it implies that the Bush administration may have already been discussing interrogation tactics that might violate the War Crimes Act. Could it be that the attitude which made the current prisoner scandal possible may have come all the way from the top? If nothing else, Gonzales seems to have felt they were treading close enough to the line that Bush should take some steps to cover his ass:
One key advantage of declaring that Taliban and Al Qaeda fighters did not have Geneva Convention protections is that it “substantially reduces the threat of domestic criminal prosecution under the War Crimes Act,” Gonzales wrote.
“It is difficult to predict the motives of prosecutors and independent counsels who may in the future decide to pursue unwarranted charges based on Section 2441 [the War Crimes Act],” Gonzales wrote.
The best way to guard against such “unwarranted charges,” the White House lawyer concluded, would be for President Bush to stick to his decisionthen being strongly challenged by Secretary of State Powellח to exempt the treatment of captured Al Qaeda and Taliban fighters from Geneva convention provisions.
“Your determination would create a reasonable basis in law that (the War Crimes Act) does not apply which would provide a solid defense to any future prosecution,” Gonzales wrote.
The original memo along with Colin Powell’s dissenting opinion can be read in the Newsweek article I linked to.
Thanks to VernR for bringing this to my attention.
Posted on 05/19/2004 at 12:19 PM 
An excerpt from the memo on the downside of not applying Geneva.
“A determination that GPW does not apply
to Al Queda and the Taleban could undermine
U.S. military culture which emphasizes maintaining
the highest standards of conduct in combat,
and could introduce and element of uncertainty
in the status of adversaries.”
It’s slippery slope once you cross the line.
Did the mindset that Geneva doesn’t apply in Afghanistan lead to the problems in the Iraq prisons?