John Bolton has quietly gotten his very own John Bolton, and his name is Tim Morrison.

Morrison possesses a hostility to negotiated restrictions on U.S. nuclear weapons that rivals Bolton’s own, as well as an expertise on nuclear issues undisputed by even his harshest critics. Among arms controllers, Morrison’s name is equivalent to Keyser Söze. A former State Department official called him “the hardlinest of the hardline on nuclear policy.”

Like Bolton—and like Keyser Söze—Morrison is effective. From behind the scenes on Capitol Hill, Morrison drove the biggest developments on nuclear weapons issues over the past decade.

If you’ve ever wondered how Barack Obama, who once talked about a nuclear-free world, ended up agreeing to pour cash into nuclear modernization, part of the explanation is that Morrison, then working for Sen. Jon Kyl (R-AZ), ate Obama’s lunch during a treaty negotiation.

Morrison then went over to the House Armed Services Committee, where he pushed new authorities for a nuclear-weapons complex whose budget ballooned, as well as GOP opposition to a host of nuclear-related treaties.

“He’s a stridently partisan person who constantly insisted on confrontation with the [Obama] administration,” said a former official at the National Nuclear Security Administration (NNSA).

A different senior NNSA ex-official said Morrison was needlessly hostile in negotiations: “It’s hard to uncouple the unpleasant part of Tim from the substantive part, and that’s why you’re hearing this negativity.”

In addition to his Hill victories, several tweets shared with The Daily Beast from Morrison’s locked account show that he enjoys owning the libs online. His Twitter avatar is a pin showing a red MAGA-style baseball cap reading MAKE DETERRENCE GREAT AGAIN. In one tweet last month, Morrison responded to a tweet from an arms controller about a push from U.S. mayors urging the administration to lead an effort against nuclear war with “hahahahahahahahahahahahahaha.”

On July 9, Morrison departed his longtime perch as policy director for the Republican staff on the House defense panel to work for Bolton as senior director for countering weapons of mass destruction on the National Security Council.

Although he called himself “not one for emotion or sentimentality” in a July 4 email bidding his Hill colleagues farewell, Morrison said leaving the committee was “the most difficult professional decision I have made to date.”

Morrison’s ascent comes amid a recent senior staff exodus that’s permitting Bolton to reshape the supremely powerful NSC in his own image. Morrison is Bolton without the mustache.

And this is their moment. A substantial amount of foreign policy now runs through nuclear-adjacent issues—and some of it through the NSC directly.

The NSC, not the State Department, is the contact group for dealing with Russia after the Helsinki summit, putting critical arms control issues like a follow-on New START treaty in the portfolio of someone who opposed and then attempted to cripple the arms-reduction accord.

Then there’s North Korea, where some experts expect hawks like Bolton to capitalize on frustration with denuclearization talks.

And then there’s Iran and the aftermath of Trump’s breach of the nuclear deal.

If that wasn’t enough, the Trump administration’s Nuclear Posture Review, which calls for fielding low-yield nuclear weapons, is aligned with Morrison’s way of thinking.

But a dozen current and former congressional aides, Obama administration officials, and nuclear experts who have dealt with Morrison—allies and adversaries alike—are quick to note a plot twist in Morrison’s ascension.

“ He always wanted to be tough on Russia. How will that translate, working in this administration? ” — Former National Nuclear Security Administration official

“He always wanted to be tough on Russia,” recalled one former National Nuclear Security Administration official. “How will that translate, working in this administration?”

Another former senior administration official was blunter: “He really hates Russia across the board.”

Morrison’s friends profess little insight into how he’ll square the Russia circle with Trump. “For someone as smart and engaged and gregarious as Tim Morrison is, there has to be a reckoning with what you believe personally and what you’re told to do professionally,” said Thomas C. Moore, a former staffer for Sen. Richard Lugar (R-IN) and a rare on-record source for this piece. “I’d have a lot of trouble saying, ‘Russia’s great, Russia’s good’ and I’d imagine he would too, but I don’t know if he’ll have to.”

Arms controllers take a different view of Russia from much of the #resistance to Trump. To them, the fact that the U.S. and Russia account for the overwhelming majority of the world’s nuclear weapons means that Russia can’t be ignored or isolated. Doing so risks escalating nuclear tensions—which is to say the risk of armageddon—and excessive hostility to Moscow sets back the broader arms-control goal of reducing nuclear weapons and negotiating agreements to constrain various aspects of their operations.

And it’s on that point where nuclear hawks like Morrison find endless frustration with arms controllers. According to the State Department—Obama’s as well as Trump’s—Russia is in violation of the Intermediate-Range Forces Treaty (INF), a Reagan-era bilateral accord banning development, testing, and fielding of ballistic and cruise missiles with ranges between 500 and 5,500 kilometers.

“That’s the challenge of bilateral agreements left over from the Cold War,” said a congressional staffer who worked with Morrison. “Republicans are willing to sign, but we don’t have a romantic attachment to them, and we insist they work.”

This staffer argued that Morrison’s opposition to nuclear arms accords is more pragmatic than ideological. Cold War-era treaties don’t anticipate emerging “holistic” threats like state-sponsored cyberattacks against nuclear command-and-control infrastructure or broader civilian infrastructure.

“If treaties can help us stop that from happening and disincentivize China and Russia, then by all means, but I think every agreement must be taken into that context—that whole outlook, in a framework of meaningful strategy to bring us back into the peaceful years of the 1990s,” the staffer said. “And that’s Tim’s philosophy as well.”

Arms controllers see a different pattern. “Tim has never met an arms control agreement he liked. He has worked to prevent them from being approved, like New START, and help kill agreements already in place, like the INF agreement,” said Jon Wolfsthal, who had Morrison’s job in the Obama White House. “I worry that he and John Bolton will continue to undermine these agreements instead of using them to help reduce the risk of nuclear conflict and [increase] transparency.”

Morrison declined to comment. A lawyer and Naval Reserve intelligence officer in his early 40s, he came onto the arms-control scene in force while working for Kyl, who in 2010 represented the opposition to the Obama administration’s New START treaty with Russia to cut both nations’ nuclear arsenals.

The Obama administration badly wanted New START, and its 30 percent cuts to the nuclear stockpile, as a centerpiece of its twin efforts to curb nuclear weapons and engage constructively with Russia.

Kyl was its principal GOP interlocutor, and he raised the cost for the treaty. In what pro-treaty Senate staffers from that era remember as a “kabuki” effort, Kyl questioned New START’s impact on missile defense, something the agreement didn’t touch. (The head of the Missile Defense Agency testified in June 2010: “The New START Treaty does not constrain our plans to execute the U.S. Missile Defense program.”)

But Kyl won a huge concession in negotiation: $85 billion over ten years for modernizing the aging nuclear weapons stockpile.

Several former nuclear-related officials caution that Kyl, and Morrison, had a point on modernization. “The nuclear complex was really in bad shape,” said one.

Two former Obama administration officials said that whoever was president at the time would have had to put more money into physical restoration of the nuclear enterprise. But Kyl got a lot, and he knew it.

“We’ve probably got all we’re going to get out of them in terms of dollar commitments,” he told The New York Times in November 2010, which described the senator as “express[ing] satisfaction.”

Kyl, who didn’t respond to a Daily Beast request for comment, got what he wanted—and then voted against New START. The administration managed to pass the treaty in a lame-duck session by a thin margin, and knowledgeable officials don’t think Kyl moved any GOP senators in the treaty’s direction.

After the GOP takeover of the House in 2010, Morrison switched over to the House Armed Services Committee. Several current and former congressional aides, as well as administration interlocutors, consider Morrison pivotal to a host of measures, usually in the annual must-pass National Defense Authorization Acts (NDAA), undermining arms control and bolstering nukes.

Among them were measures to block New START from taking force, including blocking money for treaty-authorized activities. In both 2012 and 2013, the Obama White House issued ultimately empty veto threats over the bill, citing, among other provisions, measures that would “impinge on the President’s ability to implement the New START Treaty and to set U.S. nuclear weapons policy.”

One knowledgeable official said that only a provision in a totally separate bill that became law after the 2011-era NDAA passed saved New START. Winning the nuclear funding increase during the treaty passage debate in the Senate clearly wasn’t enough for Morrison.

“ It’s Saturday night, have a drink, laugh, tell a dirty joke, something that doesn’t have to do with nuclear weapons for a change. ” — Thomas C. Moore, former staffer for Sen. Richard Lugar (R-IN)

His friend Moore considers Morrison a workaholic whose face was often glued to his BlackBerry at social events. “It’s Saturday night, have a drink, laugh, tell a dirty joke, something that doesn’t have to do with nuclear weapons for a change,” Moore said.

Several ex-officials, including those who have profound disagreements with Morrison, said he created a legacy on the committee.

The Department of Energy’s Stockpile Responsiveness Program, a creation of the fiscal 2016 NDAA, is a venue for up-to-date research on nuclear weapons design. A former senior Obama administration official said the program would not exist without Morrison and considered it an incubator for the day when the U.S. will design new warheads.

As a check on Russia’s INF violations, according to a knowledgeable official, Morrison won authorization for research and development for a mid-range missile unrequested by the Defense Department that would itself violate the treaty.

Morrison also cultivated a constituency within the military’s Strategic Command, the operational end of the U.S. nuclear complex, that sources expect will serve Morrison well at the NSC.

And while it would overinflate Morrison’s influence to consider him the critical factor, the nuclear modernization Obama ultimately agreed to spiraled to an estimated cost of $1 trillion over 30 years, and the dynamics of that spending stem significantly from the New START fight.

Not everything Morrison did succeeded. Several current and former Hill and administration officials interviewed for this piece noted that while Morrison frequently got hardline nuclear policies into the House versions of the NDAA, the Senate or conference negotiators often would tone them down. Generally that was the case with what three former Energy Department officials said were Morrison’s efforts to cleave the NNSA from the broader department, which is considered a step to empower nuclear weapons research.

But Morrison’s allies see his star as unquestionably on the rise.

“He’s part of the next generation of folks who are going to occupy positions in future Republican administrations on nuclear issues,” said Moore, who considers Morrison a likely future undersecretary of defense for policy. “He carries with him views that are sharp on a number of issues, he has engendered opposition and he’s earned it, if you will, and that’s a hallmark of people who are going on to bigger and better things.”

Arms controllers are bracing for that prospect. Mike Pompeo, the secretary of state, testified last week that the administration still doesn’t have a position on extending New START. But most people interviewed for this piece believe Morrison will oppose extending or negotiating a follow-on treaty. The NSC declined to discuss Morrison’s new portfolio.

“The National Security Council staff coordinates the efforts of departments and agencies to support the President. We don’t comment on NSC personnel,” said Garrett Marquis, an NSC spokesperson.

“When I heard Tim got the job and was going to NSC, you’re like, ‘holy shit,’” said a former senior NNSA official, “but on the other hand, who else are they going to get these days to do that job?”