Bush is doing precisely the right thing.
When our citizens are inside the sovereign territories of ICC-signee nations, then those particular individuals are subject to the laws of those nations rather than to the laws of the U.S.
What Bush is doing is getting nation after nation to modify their laws to grant U.S. vistors to their lands full ICC immunity, so that little Aunt Mary doesn't get arrested as a tourist in Germany 20 years from now and put on trial for not respecting the rights of the Afghan warlord that she shot down back when she was in the U.S. military.