American aid to foreign countries is driven by different interests, from simple humanitarianism to geopolitical positioning.

In the case of Egypt, the $1.5 billion it receives from the United States is almost entirely military aid. Its purpose, from the American perspective, is to buy influence with the Egyptian military.

U.S. policymakers across many administrations correctly have identified the military as the true power in Egypt, and they successfully have used the aid to influence Egypt's commitment to peace with Israel.

The recent military coup and subsequent bloodbath carried out by Egyptian security forces raises the question of how much influence the United States now has with the Egyptian military. Egyptian commanders rejected 16 separate entreaties by U.S. Defense Secretary Chuck Hagel to refrain from violence.

Sens. Bob Casey and Pat Toomey recently advocated cutting off that aid to Egypt, and the Obama administration appears to at least partially agree.

The question is simply whether the aid achieves anything. The amount is small compared to what Egypt receives from oil-rich Arab nations. Saudi Arabia alone is committed to providing $12 billion, as long as the current regime is in power.

Pledges of aid from other countries reflect the sectarian divisions in the Arab world. Kuwait has joined the Saudis in supporting the military-led Egyptian regime; Qatar and others back the Muslim Brotherhood-led faction that was ousted by the military.

It is highly questionable whether the U.S. has anything to gain from continued aid to Egypt. The administration should use it where it will advance American interests.