This article is from the archive of our partner National Journal

Sen. Tom Cotton had been in the Senate for little more than two months when he sat down and drafted a letter to the "leaders of the Islamic Republic of Iran."

Increasingly concerned the Congress was being forced out of the nuclear negotiations between the Obama administration and Iran, the Republican senator from Arkansas took the unusual step of composing the first version of the letter himself before bringing it to staff, and later to the Republican caucus lunch where he collected 46 of his colleagues' signatures.

What followed was a days-long stretch of backlash from a few Republicans and many Democrats, including Vice President Joe Biden, who accused Cotton of sending "a highly misleading signal to friend and foe alike that our commander in chief cannot deliver on America's commitments—a message that is as false as it is dangerous."

An irritated Sen. Debbie Stabenow mocked Cotton with an amendment days later that banned members from using Senate stationery and computers to reach out to foreign leaders if in doing so, they were "undermining the role of the President as Head of State in international nuclear negotiations."

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One former Bush administration official who spoke on background to be more candid told National Journal that "a little more life experience and a little more experience in Washington might lead to less rash decisions and statements."

But Cotton has no regrets. And he continues to speak brashly about Iran. This week, he told The Atlantic's Jeffrey Goldberg that conceding any ground to Iran could "lead to the detonation of a nuclear device somewhere in the world, if not outright nuclear war."

At least in the short term, though, Cotton's loud actions on Iran have only raised his profile and won him favor with most of his Republican colleagues, who are beginning to see the 37-year-old senator, who holds posts on the Armed Services and Intelligence committees, as a leading voice in the party of foreign policy.

"Cotton is unique because he has the most incredible background in terms of his education and what he has done in the military," Sen. James Inhofe said. "He demonstrated before he even got here that he is willing to get into areas that no one else will."

For decades, the edict on Capitol Hill was that freshman were "to be seen, but not heard." But with so many freshman senators—namely Rand Paul, Ted Cruz, and Marco Rubio—jumping into the presidential fray, many senior senators agree that there is no reason for capable newbies to stay on the backbench and wait their turn.

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"In the distant future, I don't know what else he would run for, but I think he believes in something, he's out with action; I think it is good," Inhofe said of Cotton.

But those close to Cotton say the freshman senator doesn't place a premium in gaming out a long-term strategy. He's not interested in letting excessive political discipline trump conviction.

"In his case, he believes strongly in certain things. I haven't ever really had a conversation with him about whether it is going to be unfashionable to be hawkish," said Bill Kristol, the editor of The Weekly Standard, who has been corresponding with Cotton since he deployed with the Army in 2006.

Kristol says that what has impressed him about Cotton is that he has been aggressive about seeking out guidance from those who have been around the Beltway longer. Kristol says he is one of several conservatives Cotton bounces ideas off of. Others include former GOP whip Sen. Jon Kyl of Arizona. 

"Like any other intelligent senator, he is not afraid to pick up the phone," Kristol said. "Some people come to Washington, it doesn't occur to them they are a senator, they can call anyone they want, they can get people to come for lunch or stop by and brief them for two hours."

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It's a characteristic that senior members also have picked up about Cotton. They say that while Cotton is competent and confident, he is sensitive to the unspoken social cues of the Senate.

"His approach is different," Sen. John McCain said. "I don't know anyone who really disagrees with what Tom Cotton is doing, and there was significant disagreement with shutting down the government."

Cotton's precociousness, however, didn't suddenly emerge. When he was serving in Iraq in 2006, Cotton wrote a screed against The New York Times, arguing that the paper's reporting put his soldiers' lives in jeopardy. He hoped that by the time he got back from Iraq, the reporters would "be in your rightful place: not at the Pulitzer announcements, but behind bars."

And just a few months after he was sworn into his House of Representatives seat, Cottom gained notoriety on the House Foreign Relations Committee for staking out positions that ran counter to many others in his party, who were war-weary and open to limiting U.S. intervention in the Middle East and the rest of the world.

In a 2013 interview with CNN, Cotton—who served in both Iraq and Afghanistan—told Candy Crowley that while it got off to a rocky start, the Iraq War was "a just and noble war."

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And in an April 2013 interview with Politico, Cotton said "I think that George Bush largely did have it right, that we can't wait for dangers to gather on the horizon, that we can't let the world's most dangerous people get the world's most dangerous weapons, and that we have to be willing to defend our interests and the safety of our citizens abroad even if we don't get the approval of the United Nations."

While for a short time it looked as though the Republican Party was taking a turn on foreign policy and some in the House were following in the footsteps of the libertarian-minded Paul, Cotton fit a mold much more similar to the warhawks of the Senate.

"I encouraged him, when he was in the House, to run for the Senate," said McCain, who brought Cotton to national security conferences and pushed him to consider higher office. "I view him, [Dan] Sullivan, and Joni Ernst as our next generation of national security experts. That is why I spend a lot of time with him."

While some Democrats have questioned his tactics, Cotton has landed on a rare and precious point in politics: a time when his convictions appear to align with the underlying security concerns felt by many in the the country.

Two years ago, when Cotton was in the House, members appeared reticent to give the president authority to engage militarily in places like Syria. But the emergence of ISIS, instability in Ukraine, and shifting relations with Iran have made voters reconsider an aggressive posture toward foreign policy.

Following a briefing on Iran from Secretary of State John Kerry on Tuesday, Cotton—who tends not to engage in the hallway interview routine on Capitol Hill, meandered toward the mics, taking a place in front of a row of television cameras. Speaking in his nasally yet forceful tone, he stared down a spray of cameras and said, "We just received a classified and technical briefing from the administration, but there is nothing classified or technical about the fundamental flaw with the president's proposal. It puts Iran—the worst state-sponsor of terrorism—on a path to a nuclear weapon."

He answered reporters' questions for a few minutes. When asked for his thoughts on interjecting himself into issues of such significance so soon, Cotton paused, then raised his head.

"I think this question is not a matter of how long someone has been in the Senate or the Congress or how long [someone] has been serving in the government, but who is right and who is wrong about this matter."

This article is from the archive of our partner National Journal.

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