The U.S. is not a part of the International Criminal Court and unlikely to sign up anytime soon, but the Obama administration is making an effort to cooperate more with it. Top State Department lawyers are taking part in a review conference meant to take stock of the court's proceedings so far. The court needs countries to help get some of the indicted war criminals to face trial. Another issue to be discussed is how the court defines "aggression." U.S. officials are worried that the U.S. could be exposed to prosecutions if the crime of aggression is too broadly defined.