"a war crime is a war crime..." : The rule of law between nations has been a legal fact since Hugo Grotius wrote his "De Jure Belli ac Pacis" in 1625. It applies for all the countries in the world with no exception. And because it's a body of law it stands above politics. The classification of war-crimes can thus never be handed over to dictators and communists. This is a task for the international jurist-community.
Just because the USA doesn't recognize the ICC doesn't mean your country isn't regulated by the international law. The difference between national and interational law is that international law can't be enforced the same way national law can. But with the ICC we can have such a instrument.
As for the benefits of american support to the ICC: The court could be houndred-fold more effective. Then we could use the court to go after the REAL war-criminals: goverments and organisations who aid and support terrorists in the middle east and asia.
Bovine Excrement!
Eurpoean Socialists have made it quite clear that they will "abuse" the ICC for purely political purposes, and there is already a precedent. Ask Belgium.
Our country is NOT "regulated" by "international law" in any way. Our country signs treaties with such understandings with other countries.
No matter how you try to classify that supposed "body of law", it can and WILL be used with politics being the driving force behind it.
No matter how you attempt to justify the ICC, it is and will always be a defunct body that is driven primarily by politics, much the same as the UN.
These lame ideas sound oh-so-good on paper and to "intellectuals", but in practice it always ends up turned against "good" and put to use for "evil".
The best way to "go after" war criminals is simple: Hunt them down and kill them. IMHO