As the U.S. scrambles to convince Israeli Prime Minister Benjamin Netanyahu to extend the moratorium on building Israeli settlements, which will expire on Sunday, American policymakers should be equally concerned about Hamas if settlement building resumes, say Middle East experts.

The newest iteration of Israeli-Palestinian peace negotiations that began earlier this month is facing its first major hurdle on a final status issue. Netanyahu is under heavy pressure from a multitude of actors, including the United States, to extend the ten-month moratorium on settlement building, while settlers and factions of his own Likuud coalition are demanding settlement construction continue.

While it is likely Netanyahu will wait until the last possible moment to make his announcement, the U.S. is equally unsure of what Hamas will do should construction resume.

When Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas were preparing to restart direct negotiations on final status issues at the White House with President Barack Obama and Secretary of State Hillary Clinton, on August 31 Hamas launched a deadly attack against settlers in Hebron, killing four Israeli settlers.

The attack was condemned by all sides in the negotiations including Abbas, who ordered one of the largest crackdowns on Hamas in the Palestinian Authority's history.  The arrest of more than 300 individuals believed to have ties with Hamas in the West Bank also came with allegations of torture by PA intelligence officers.

But as senior fellow for Middle East studies at the Council on Foreign Relations Mohamad Bazzi points out, “There’s a reason Hamas waged an attack in the West Bank and there’s a reason settlers were the target.”

Hamas has routinely signaled that they view settlement construction as the primary symbol of Israeli occupation. Hamas’ military wing, Ezzedeen Al-Qassam Brigades, claimed responsibility for the attack in a communique on its website stating that, “These operations are part of the repelling operations against the occupation assaults on Gaza Strip and West Bank, and as a response for the ongoing aggression against Palestinian people.”

Middle East experts say the Hamas-Israeli settlement issue is just one reason the U.S. needed to include Hamas in the negotiation process—even if not formally—and exemplifies the larger strategic problem the U.S. has in dealing with Hamas.

Shadi Hamid, Director of Research at the Brookings Institution’s Doha Center and fellow at the Saban Center for Middle East Policy, says that the U.S. suffers from “the inability—or perhaps unwillingness—to think clearly and strategically about the Hamas factor.”

The lack of U.S. strategy regarding Hamas is one that has the potential to jeopardize American efforts as it attempts to push forward on direct talks between Palestinians and Israelis, but it appears the U.S. is content remaining silent on the Hamas issue.

Hamas, while remaining on the State Department’s list of Foreign Terrorist Organizations, effectively rules the occupied territory of Gaza, populated with more than 1.5 million Palestinians.

“Hamas isn’t going to disappear,” says Hamid, “so the question of what to do about it is just going to linger until someone comes up with a creative, workable path forward.”

Brian Katulis of the Center for American Progress suggests that one strategy might be creating enough carrots and sticks to change, or at least temper, Hamas’ typical strategies.

“Hamas is likely to continue its strategy of resisting the efforts to achieve a negotiated deal between Israel and the Palestinian Authority,” says Katulis, “unless some set of incentives and disincentives can effectively reshape the movement’s calculations.”

But Hamid notes that the U.S. strategy hasn’t changed in the two decades of negotiations since the Oslo Accords were signed in 1991.

“It still has a “West Bank-first” policy,” says Hamid, “to show Palestinians that they’re better off under Fatah rule.”

This hope relies on the assumption that Palestinians will draw the kind of conclusion the State Department thinks it should. However, as Hamid notes, “instead of blaming Hamas for not supporting peace, they may just decide to blame us, or Israel, instead. It wouldn’t be the first time.”

The U.S. has often miscalculated the role of Hamas in Palestinian politics, including the 2006 parliamentary elections in which Hamas crushed Fatah with 74 seats won over Fatah’s 45. It was with Abbas’ reluctance and then-Israeli Prime Minister Ariel Sharon’s outright objection that the Bush administration insisted Hamas participate in the elections, dramatically underestimating the party’s popularity among Palestinians.

Hamid points out that, “So far, the little the Obama administration has said about Hamas suggests it doesn’t have a plan and doesn’t plan on getting one.”

But Aaron David Miller, Public Policy Scholar at the Woodrow Wilson Center for International Scholars, said leaving Hamas out of the negotiations is no mistake, calling it a “clear, determined policy decision.”

“Including Hamas in the negotiations would drive the Israelis crazy and likely cause a further divide among Palestinians,” said Miller, a former negotiator on Israeli-Palestinian peace for the State Department.

“The Palestinian National Movement is in a state crisis,” says Miller. Hamas and Fatah “are in two different territories, with two different streams of funding, and with two different governing structures—and there’s no way to fix that now.”

Hamas and Fatah have been divided since Hamas violently seized control of Gaza in June 2007, despite attempts at reconciliation talks over the last two years brokered by neighboring Egyptian President Hosni Mubarak.

At a briefing at the New America Foundation in Washington on Thursday, Palestinian Prime Minister Salam Fayyad said that the lack of Palestinian unity is a “political division” and not “about geography.”

The official Palestinian representation in Washington, the PLO Mission to the United States, is downplaying the potential problem of excluding Hamas, insisting that Hamas accepts the role of the PLO as negotiator.

Dr. Amal Jadou, the Deputy Chief of Mission, told Raw Story that “Even before Hamas’ takeover of Gaza, and when it was a full partner in the national unity government, it accepted that negotiations with Israel fall under the PLO’s mandate.”

According to Jadou, Hamas has also accepted a two-state solution in line with the 1967 borders, if it is approved by the Palestinian population in a national referendum. “East Jerusalem, the West Bank and Gaza Strip represent one political and geographical entity,” she said, “They are all occupied territories and negotiations are aimed at ending the occupation that began in 1967.”

Jadou added, “President Abbas has been consistent in insisting that any agreement will be put to the people for a vote in a national referendum.”

But, as Bazzi points out, to some degree Hamas has to be on board to even allow the referendum to take place in Gaza.

And what happens if it’s an amazing [Israeli-Palestinian] agreement, but Hamas doesn’t allow the referendum because they view it as a strange?” asked Bazzi, “What happens then?”

Allen McDuffee is a New York-based journalist and blogs at Think Tanked.