PRESIDENT BUSH and Palestinian leader Mahmoud Abbas will have a novel topic on their agenda when they meet today, in addition to more enduring issues such as Palestinian violence against Israelis and Israel's reluctance to ease a stranglehold on Palestinian territories. With Palestinian legislative elections planned for January, Mr. Bush will press Mr. Abbas on his plan to allow candidates from the extremist Islamic movement Hamas to run and maybe even join the government that will be formed afterward -- even though Hamas has refused to renounce violence as a means of establishing an Islamic state and extinguishing Israel.

There are big stakes in this discussion. Israel and its advocates in Washington have launched an aggressive campaign to convince the administration that Hamas must be banned unless it disarms and modifies its ideology. Israeli Prime Minister Ariel Sharon has threatened to disrupt the January election if Hamas participates. The Israelis warn that an unreformed Hamas will use the election to ensure that its weapons and extreme agenda are not marginalized by Mr. Abbas's moderate, reformist movement. They point to Lebanon, where Hezbollah has used the political leverage it won in recent elections to protect its heavily armed militia, despite a United Nations resolution ordering its disarmament.

Mr. Abbas, president of the Palestinian Authority, agrees in principle that Hamas should abandon violence; he argues that he has pressured the Islamists into observing a cease-fire for most of this year. But his aides say that Palestinian security forces would probably lose if they challenged Hamas. Mr. Abbas's strategy is to do his best to defeat Hamas at the polls, then ask the new legislature to require all armed groups to disband. He hopes Palestinian public opinion will force the militants to comply. Recent polls show that up to 60 percent support Hamas's disarmament.

For the United States, the handling of Hamas is inseparable from a regional policy of democratization that, in its essence, is about channeling Islamic movements into electoral politics and away from terrorism. The strategy won't work if the Islamists refuse to give up terrorism, but it will also fail if, in countries such as Lebanon and Egypt as well as in the Palestinian territories, Islamic parties are prohibited from peaceful political competition. Perhaps that's why the administration so far has gingerly separated itself from Israel on this issue. Officials say Mr. Bush will press Mr. Abbas to pass and to apply the laws he plans before the elections and to exclude Hamas candidates linked to violence. But if the Palestinian leader persists in his strategy, the administration appears inclined reluctantly to go along rather than repudiate a moderate Palestinian leader or a potentially groundbreaking Middle East election.

That seems like the right choice for now. But if Mr. Bush is going to keep betting on Mr. Abbas, he should do more to help him succeed. Palestinian security forces cannot confront Hamas partly because they lack adequate training and weapons. Mr. Abbas also suffers politically from Mr. Sharon's foot-dragging in concluding agreements to allow the movement of goods and people from Gaza and from Israel's recent redoubling of West Bank roadblocks it promised to lift months ago. The United States can use its influence to ease those problems and to accelerate Palestinian economic reconstruction between now and January. Meanwhile, it can more clearly articulate, around the region, the principle that Islamic movements -- including those with fundamentalist ideologies -- must have a place in Muslim democracies, but that they must also check their guns at the door.