The first-ever participation of Hamas in the Palestinian elections on Wednesday poses significant policy challenges to the United States, Europe, Israel and the region.

Hamas calls for the destruction of Israel and is designated a terrorist organization by the U.S. and the E.U. A Hamas victory could lead to the creation of the first Sunni jihadist state in the modern Middle East, paralleling the Shiite theocracy in Tehran. Hamas is a local offshoot of the Muslim Brotherhood, a regional extremist network that threatens Egypt, Jordan, Lebanon and Iraq. While Hezbollah represents only one sect in Lebanon, Hamas threatens to overwhelm the entire Palestinian Authority.

Hamas is running neck and neck with the ruling Fatah party and will likely enjoy a strong showing in Wednesday????????s elections. Palestinian Authority President Mahmoud Abbas will be unable to form a government on his own and will be forced into protracted negotiations with Hamas. This transitional period, which may last many weeks, will be fraught with perilous political and security implications, especially on the eve of Israel????????s elections, traditionally a period of heightened terrorism. The Palestinian electoral crisis, combined with Iranian, Syrian and Hezbollah-sponsored terrorism could lead to a ???????perfect storm.???????

The United States, Europe and Israel have made clear that Hamas participation in the Palestinian Authority would undermine the prospects for peace and lead to the Palestinian Authority????????s isolation. There is only one way to resolve this. In the words of the international Quartet, Hamas must “renounce violence, recognize Israel????????s right to exist, and disarm.??????? Washington????????s challenge in the coming weeks will be to lead an international effort and enforce this line in the sand.

The Dispatcher is a new contributor at Publius, focusing on the Middle East. It is a pseudonym for two foreign policy specialists in that region, who must remain anonymous. They also blog at Vital Perspective.