Nearly one year after a group of six nations led by the United States reached a nuclear deal with Iran, one of the loudest critics of the agreement is warning about the “consequences” of an accord that he believes has emboldened Tehran to provoke terror across the world.

Sen. Tom Cotton, a freshman Republican from Arkansas, injected himself into the Iran nuclear debate back when the Obama administration was negotiating the agreement by writing a letter to Iranian leaders declaring that the deal could be thrown away by the next president.

Now that the deal has been implemented, and Iran has constrained its nuclear capability in exchange for billions in sanctions relief, Cotton says he has seen enough to confirm his long-standing fears.

“What we’ve seen in the past year is the more immediate, non-nuclear consequences of the deal, which is the empowerment of Iran throughout the region and the consequences that has for U.S. interests and our allies,” Cotton said Wednesday during a briefing for reporters at The Heritage Foundation.

Referencing specific aggressive behavior from Iran, Cotton mentioned Tehran’s involvement in the wars in Syria and Yemen, its continued support for U.S.-declared terrorist groups Hezbollah and Hamas, and its recent ballistic missile tests.

“Over the last year we’ve seen nothing but the continued aggression of Iran, and the consequences of the nuclear deal with Iran are growing worse and spreading farther out, and they have an impact not just inside the Middle East but all around the world,” Cotton added.

But even as critics like Cotton sound off against the deal in public, Republicans in Congress haven’t passed an Iran-related bill since the agreement formally went into effect in January.

Cotton hinted that Congress may act soon, and he defended his own attempts at action.

Last month, the Senate voted down Cotton’s amendment to an energy spending bill that would have prohibited the U.S. from buying heavy water—a key component in nuclear weapons development—from Iran.

On Wednesday, Cotton also expressed support to reauthorize the Iran Sanctions Act, a core element of U.S. sanctions on Tehran that punishes foreign entities supporting Iran’s energy sector and purchase of advanced conventional weapons.

While some have speculated that Iran would view the renewal of the Iran Sanctions Act—which expires at the end of 2016—as a violation of the nuclear deal, the Obama administration has expressed openness to extending the legislation.

Sen. Bob Corker, R-Tenn., the chairman of the Senate Foreign Relations Committee, is preparing broader sanctions legislation, along with pushing for the extension of the Iran Sanctions Act.

Micah Johnson, Corker’s communications director, told The Daily Signal the proposed legislation would expand sanctions against Iran on issues unrelated to the nuclear agreement, like its support for terrorism and ballistic missile tests.

The House Foreign Affairs Committee is working on similar legislation. Yet these actions could have little practical impact—and be resisted by the Obama administration—because they may give Iran less incentive to comply with the nuclear deal.

“I think Obama has the votes to veto and block any legislation that he sees as undermining the nuclear agreement,” Gary Samore, Obama’s former chief adviser on nuclear policy, said.

“Obama won’t allow that to happen because it would give Iran an excuse to renege on the deal,” Samore told The Daily Signal in an interview. “So whatever Congress does at this point seems pretty irrelevant, until there is a new president.”

Iran is already declaring itself unsatisfied about what it has gained under the nuclear deal, as it has struggled to reintegrate with world markets—even after the removal of U.S. and European sanctions.

“The Iranians are unhappy with the degree of sanctions relief they are getting,” Samore said. “The European banks remain very cautious about investment and handling big financial transactions with businesses connected to Iran because there’s still very restrictive non-nuclear sanctions that remain in place on Iran, and that creates legal liability for the banks.”

While Samore doesn’t think Iran is angry enough to renege on the nuclear deal, Cotton argues that Tehran’s frustrations put into question the durability of the agreement. Most of the limits on Iran’s nuclear program expire after 10 to 15 years.

“We’ve seen over the last six months in particular that the leadership of Iran does not view the deal as settled,” Cotton said. “They view it as something subject to continual negotiation and more demands.”

For now, Samore says, Iran is fulfilling its commitments under the nuclear deal, eliminating centrifuges and most of its uranium stockpile, redesigning a research reactor designed to produce plutonium, and allowing international inspectors access to its facilities.

“The agreement has rolled back Iran’s nuclear capacity, so from that standpoint the agreement is a success,” Samore said. “It has achieved what it was intended to achieve, removing the imminent threat of Iran acquiring nuclear weapons. But for those thinking the agreement would be transformative, and have some positive effect on Iran’s domestic policy and foreign policy, that simply hasn’t happened.”

Though proponents of the deal with Iran say it was only intended to address the nuclear issue, Cotton is worried about Tehran’s aggressive behavior in other arenas, and he believes Congress needs to draw a line where he says the Obama administration won’t.

“There has been certainly near-term no sign of moderation from Iran,” Cotton said. “And we are seeing time and time again the imbalance on the two sides of the deal. At least the U.S. government, and maybe the entire Western negotiating partners, want the deal much more than Iran does.” (For more from the author of “Nearly a Year Since Nuclear Deal, Tom Cotton Alarmed by ‘Empowerment of Iran'” please click HERE)

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