WASHINGTON — As they prepare for battle over the new deal to limit Iran's nuclear program, the accord's supporters and foes are calibrating strategies based on their reading of Americans' conflicted views about the Islamic Republic.
American war-weariness forms a big part of the Obama administration's campaign for the accord, a preliminary agreement to curb Iran's disputed nuclear program. Administration officials have said that without a diplomatic deal, the country would be on a "march to war."
For now, the administration appears to have the upper hand. Many skeptics of the deal, who issued sharp criticism shortly after its announcement, have since muted their words.
Instead of attacking the agreement directly, opponents have pinned their hopes on continued American suspicion of Iran and its leaders. They expect the government in Tehran to fail to meet its obligations under the agreement and are poised to go on the offensive if that happens.
"Critics of the deal are reluctant to attack it too frontally because they realize how popular it is," said Dylan Williams, legislative director for J Street, a liberal pro-Israel group that supports the deal.
Polls suggest that support for the deal is strong now but could easily decline. Americans are deeply reluctant to embark on a new Middle East war. At the same time, however, Americans have consistently held negative views of Iran since the hostage crisis during the Carter administration.
For years, many Americans have said in surveys that they would support military action if that was necessary to prevent Tehran from obtaining a nuclear bomb. A June poll by the Pew Research Center found 64% support among Americans for such intervention.
Now, however, a Reuters-Ipsos survey released Tuesday showed 44% of respondents supported the new accord; 22% opposed it. If the deal failed, 49% would favor more sanctions, 31% wanted more diplomacy, and 20% wanted to turn to military force.
"The appetite for military engagement anywhere is very low," said pollster Julia Clark of Ipsos. After two wars that were far longer and costlier than expected, "we in the public feel burned."
Even so, Clark said, opinions on the deal could change because Americans are uncertain about its complexity and have negative views about Iran, which has been at odds with the United States since the 1979 revolution. She noted that about one-third of the poll's respondents weren't sure how they felt.
"There's real hesitation here," she said.
The preliminary agreement between Iran and six world powers, including the U.S., was announced Sunday in Geneva. It would temporarily ease some of the sanctions that have crippled Iran's economy in return for a halt to key aspects of the country's nuclear program.
The deal is intended to allow time to negotiate a comprehensive agreement on the nuclear program. Iran insists its nuclear program is for peaceful purposes, but officials of many countries believe the effort is aimed at developing at least the capability to build a nuclear weapon.
Opponents of the deal have called for new sanctions, saying that greater pressure could force Iran to yield more. The Obama administration calls that unrealistic and says new sanctions could derail any chance for diplomacy to succeed.
In a videotaped message designed to sell the deal to Congress, Secretary of State John F. Kerry said the negotiators had moved to prevent Iran from acquiring a bomb "in the most effective way: We did it through diplomacy."
A number of key lawmakers who have criticized the agreement have said they support additional sanctions but are ready to hold off unless signs emerge of Iran not holding up its part of the deal.
Sens. Robert Menendez (D-N.J.), chairman of the Senate Foreign Relations Committee, and Saxby Chambliss (R-Ga.), ranking minority member of the Senate Intelligence Committee, called for deferred sanctions.
Israeli officials have strenuously opposed the accord, and lawmakers who support Israel have been prominent among the deal's critics. But statements from major pro-Israel organizations in the United States have been relatively mild.
The American Israel Public Affairs Committee, the leading pro-Israel lobby, cited "serious concerns" that Iran could still develop a bomb even if the two sides reached a final deal. But AIPAC said new sanctions should be imposed only if Iran violated the agreement or failed to agree to an acceptable final deal.
Another major American Jewish group, the Anti-Defamation League, said it was "deeply concerned" about the "flaws" in the deal. But instead of calling for sanctions, it committed itself to "work to promote a final agreement which ensures Iran is incapable of building a nuclear weapon."
An official of another pro-Israel group, who declined to be identified, citing the sensitivity of the issue, said many in the organization were reluctant to be seen as trying to block the deal, especially at a time when the issue was straining relations between Israel and the Obama administration.
Mark Wallace, chief executive of the advocacy group United Against Nuclear Iran, acknowledged that the deal had support, but predicted that the backing would fade "when people begin to digest and understand the agreement."
Clark, of Ipsos, said that could happen. The Reuters-Ipsos survey found "some hedging" in reactions because of the uncertainty about the details of the deal, she said.
But the uncertainty of public opinion creates risks for both supporters and opponents, she said. "If there's a sudden great surge of confidence, people may not want to be on the record as being against it."