The Washington Post | Adam Taylor: President Trump is no fan of the “disastrous” Obama-era nuclear deal with Iran. Though his administration recertified Tehran's compliance with the deal this month, it did so only after a heated internal debate. Even after its recertification, Trump warned this week that Iran had become “emboldened” and that it could face “big, big problems” if it violated the terms of the deal.

The U.S. president isn't the only party to the deal worried that the agreement isn't being adhered to, however.

According to new polling data, a majority of Iranians consider new U.S. sanctions on their country over its missile program a breach of both the letter and the spirit of the nuclear agreement. At the same time, many Iranians surveyed say that if the Trump administration abrogates the deal, their government should retaliate by restarting aspects of its nuclear program.

The poll is part of a series conducted by the Toronto-based IranPoll for the Center for International and Security Studies at the University of Maryland. The surveys were conducted through random dialing of landline phones, with a sample size of more than 1,000 in each instance, and has a margin of error of plus or minus 3.1 percentage points. IranPoll President Amir Farmanesh reports that the sample closely matched the regional, age, sex, education and ethnic makeup of Iranians per census data.

Though conducting opinion polls in Iran is difficult — the country has limitations on freedom of speech, and it is not always clear whether people feel free to voice their true opinions — the IranPoll series has become one of the best snapshots of public opinion in Iran. Farmanesh says his organization is “proud of providing the most accurate prediction of the outcome of Iran’s May 2017 presidential election,” with its survey predicting incumbent Hassan Rouhani's win within two percentage points of the final results.

The latest data from IranPoll found that overall, a majority of Iranians still support the 2015 nuclear deal, known as the Joint Comprehensive Plan of Action, or JCPOA, reached between Iran and six world powers. Sixty-seven percent of Iranians surveyed in the poll, conducted in June, said they strongly or somewhat approved of the deal, versus 27 percent who disapproved in some capacity. These numbers improve upon numbers from earlier in the year and in 2016, though they are less positive than those shortly after the agreement was reached — 75 percent of Iranians were found to support the agreement in August 2015.

However, there are still considerable signs that the JCPOA has not met Iranians' expectations. More than 70 percent said living conditions had not improved in Iran in the two years since the deal was signed. Of those who felt their living standards had improved, just 4 percent described the positive changes as “a lot.”

Notably, many Iranians took a hard line on other issues related to sanctions and the limits of the JCPOA. A particular subject of dispute between Tehran and Washington is Iran's ongoing ballistic missile program, which the United States has said violates a U.N. resolution on ballistic missiles and the spirit of the nuclear deal. State media reported that Iran launched a satellite-carrying rocket on Thursday. The State Department called it a “provocative action.”

Earlier this month, the United States imposed new sanctions on Iranian individuals and companies it says played a role in these missile tests. President Hassan Rouhani has said that Iran will respond if a bill in the U.S. Congress imposing sanctions on people involved in the country's ballistic missile program were to become law. “If the enemy breaches parts of the deal, we will breach parts of it,” Rouhani said in a Wednesday cabinet meeting broadcast by state TV, according to the Associated Press. “If they breach the entire deal, we will breach it in its entirety.”

A bill that strengthens sanctions on Iran for its missile program, as well as similar measures that target North Korea and Russia, cleared Congress on Thursday, though it still requires Trump's signature.

Asked about proposed U.S. sanctions in June, 49 percent of Iranians said the measures would go “against the letter and the spirit of the JCPOA,” and 24 percent said the sanctions would go only against the spirit of the agreement. Responding to a separate question, 55 percent said Iran should continue testing ballistic missiles and insist that the issue is not negotiable.

The poll found that 63 percent of Iranians consider demands to reduce missile testing unacceptable. Compared with other demands listed by interviewers, only recognition of Israel was viewed as unacceptable by a larger proportion of the population (66 percent), while limitations on the use of the death penalty in Iran for crimes other than murder appeared to be the least controversial demand (though 48 percent still considered this demand unacceptable).

Iranians were more evenly split on how to respond if the United States took actions against Iran that were “in violation of the JCPOA.” Fifty-five percent said Iran should retaliate by restarting those aspects of its nuclear program that were shut down, while 41 percent said Iran should seek to resolve the issue by talking to the United Nations. Iranians also strongly rejected Trump's calls to renegotiate the JCPOA, with 67 percent saying such a proposal should be refused outright.