There is, at least, one ‘principled’ reason why the United States ought to ratify the Rome Statute which would join us with the International Criminal Court, namely, that in order to us to be consistent requires that we do this.
First, the United States has a long history of supporting international criminal tribunals. American judges and attorneys played key roles in the Nuremberg, Tokyo, and Rwandan trials. The US had supported the establishment of the ICC until the provision giving the Security Council the power to veto cases remanded to the Court for adjudication was rejected.
Second, the United States has a long history of participating in international politics, particularly politics concerning international human rights. In fact, American diplomats, American ambassadors, American delegates to the UN, and in particular, Eleanor Roosevelt, played a key role in convincing the UN to adopt the Universal Declaration of Human Rights in 1948. Because we have a long history of supporting international criminal tribunals, and because we have an even longer history of participating in international politics, in the absence of cogent reasons for non-ratification of the Rome Statute and withdrawal from international politics, the United States ought to ratify the statute and to continue its participation in international politics.