US President Barack Obama's choice for secretary of defense is highly skeptical that military action against Iran would effectively blunt its nuclear program.
The academic writings of Ashton Carter, nominated on Friday in a small White House ceremony, reveal an alignment on this policy matter with the president, who has said publicly over the years that diplomacy is the most "durable" course of action with Iran.
"Military action must be viewed as a component of a comprehensive strategy rather than a stand-alone option for dealing with Iran's nuclear program. But it is an element of any true option," Carter wrote in a June 2008 paper for Harvard University's Belfer Center. "Military action by itself will not finish the problem."
At best, he writes, an attack would serve to delay Iran's nuclear program for a period roughly two years. The essay was published before the election of Iranian President Hassan Rouhani in 2013, or the beginning of talks between Iran and world powers later that year.
Carter goes on to outline broad costs to the United States of such an attack.
It could lead to an "irreversible effect on Iranian opinion," he wrote. "It could take the form of increased [Iranian] meddling, through Hezbollah and other proxies in Iraq, Lebanon, the West Bank and Gaza."
US interests across the region, including its embassies and staff in countries suspected to be complicit, would be targeted, he says.
Carter's work at Harvard focused on nuclear non-proliferation efforts, particularly on the fear of loose nuclear materials and how to track and obtain them.
The alternative to the diplomatic table, he wrote in the paper, "broadly speaking, is a strategy of containment and punishment of an Iran that ultimately proceeds with its nuclear program."
"A variety of military measures— air assault, blockade, encirclement, and deterrence— could be elements of such a containment strategy," he continued.
Greg Rosenbaum, chair of the National Jewish Democratic Council and a colleague of the secretary-designate at Harvard Kennedy School, says Carter "has perhaps been more of an advocate of the military option to prevent attempts to obtain nuclear weapons."
"He clearly notes that it alone would not stop an Iranian nuclear weapons program," Rosenbaum says. "He sees it as an array of options that must be on the table."
Rosenbaum made note of Carter's tight, behind-the-scenes work on the US-Israel relationship: as part of the Pentagon's Defense Advisory Acquisition Group (DAAG), Carter was instrumental in guaranteeing the transfer of US-made F-35 fighter jets to the Jewish State.
"He's played a key role in maintaining Israel's qualitative military edge," Rosenbaum said.
In the 2008 paper, Carter addressed the prospects of an Israeli strike on Iran— a prospect heightened once again last month, as The Jerusalem Post published renewed consideration of an Israeli strike should world powers agree on a deal with Iran in Vienna considered insufficient to Jerusalem.
Carter focuses on Israel's inability to repeatedly strike Iran's facilities. Israel's mission would be restricted, he wrote, due to the hostile air space Israeli jets must cross in order to enter Iran.
"An Israeli strike would be a small, one-flight affair," Carter wrote, adding: "The costs to the United States of an Israeli strike on Iran's nuclear program might... be almost as large as the costs of a US strike."
Responding to this article, the White House noted that its policy against containment of a nuclear Iran is well established: The president, and his national security team, have repeatedly vowed to prevent Iran from ever acquiring a nuclear weapon in the first place.