Jonathan Fanton
Former MacArthur Foundation President

To the Editor:

''Mocking the Powerless and the Powerful'' (editorial, Sept. 21) correctly calls on the Security Council to demand that Sudan arrest former Interior Minister Ahmad Harun and turn him over to the International Criminal Court in The Hague. Mr. Harun is charged with financing and arming janjaweed militias responsible for the deaths of 200,000 people in Darfur and driving 2.5 million more from their homes.

The Harun case raises a larger question: Who is responsible for enforcing the I.C.C.'s arrest warrants, not just in Sudan, but in Uganda and the Democratic Republic of Congo as well?

Joseph Kony, leader of the Lord's Resistance Army in Uganda, remains holed up in Congo with his troops, drawing out a peace process that began more than a year ago. Mr. Kony and his generals have abducted more than 24,000 children and conducted a campaign of mutilation and terror in northern Uganda that displaced two million people.

The court's first indictments in October 2006 were for Mr. Kony and three of the L.R.A. leaders. All are still at large.

The International Criminal Court is the lynchpin of an emerging international system of justice that should make it clear to those who would commit genocide and other crimes against humanity that the age of impunity is drawing to a close. But to fulfill that promise and deter future evildoers, the court's warrants must be enforced.

The Security Council and particularly France and Britain, which are members of the court, should take the lead. Unless the arrest warrants are enforced, the court will not succeed, and a moment in history to create a more just world will be lost.