The peninsula is “bristling with missiles like a hedgehog,” said Jeffrey Lewis, director of the East Asian Nonproliferation Program at the James Martin Center. “The scale raises this question...are they just defending the peninsula or using the peninsula to project power through the Black Sea?” Either way, Lewis said, “The scale is really quite something.”

He believes the buildup is not merely temporary: “This is a real investment in the defense of the Crimean peninsula.”

Meanwhile, Ukrainian officials say that Russia is upgrading four Crimean facilities to hold nuclear weapons, including one at Feodosia. The Ukranian Ministry of Foreign Affairs has been distributing a briefing that lists the sites since at least December. (Mustafa Dzhemilev, a member of Parliament and a leader of the Crimean Tarter movement, has been saying since 2016 that Russian nuclear weapons already are on Crimea, a view the Ukranian government has not endorsed.)

The U.S. intelligence officials declined to endorse or refute this, saying that intelligence on the presence of nuclear warheads on the peninsula was classified.

But they did note that Crimea has hosted Russian nuclear-capable aircraft and ships. And they added that Russia is not forbidden by any treaty from deploying nuclear weapons to areas that it views as its sovereign territory — a view that Russian officials have been offering since 2015.

What’s It All For?

The deployment of the S-400 missile systems on Crimea is mostly defensive, the first U.S. intelligence official said, reflecting that Moscow may have “a sense of vulnerability about a Ukranian-NATO effort to retake it by force.”

“Russian force modernization focuses mainly on improvements to air and naval and coastal defense forces to create this anti-access area denial zone, as you pointed out with the deployment of the S-400s,” the official said. “We’ve seen the deployments of coastal defense missile batteries. We’ve seen the modernization of their air forces and naval forces.”

But others, including a second intelligence officer interviewed by Defense One, see the Black Sea Fleet modernization as intended to have effects far beyond Crimea.

“The reinvigoration of the Black Sea Fleet is not contained to the Black Sea,” the second official said. “A lot of the stuff for their operations in Syria was coming out of the Black Sea, so we would see a heightened [operational] tempo as a result for that...Any time it becomes apparent we might strike into Syria as a response for chemical weapons use or something like that, you’ll see ships coming out of the Black Sea, moving down into the Mediterranean.”

The idea that Russia uses Crimea to project power was echoed by Ben Hodges, Pershing Chair in Strategic Studies at the Center for European Policy Analysis.

“This is their launching pad into the Middle East and Eastern Mediterranean. It’s essential for their resupply into Syria, [which] has to come through the Black Sea, through the Dardanelles,” said Hodges, formerly the 3-star commanding general of U.S. Army Europe.

He added that Russia is using its enlarged Black Sea Fleet to constrain Ukraine.

“Russia, being a Black Sea littoral nation, has a sovereign right to move on the sea. But by illegally annexing Crimea and assaulting Ukraine Navy ships in November, they are positioning themselves to deny freedom of navigation on the Black Sea. That’s a huge concern.”

The increased regional military presence also helps Russia evade sanctions levied by the United States and the European Union after the UN voted to condemn the annexation, Hodges said. For example, Turkish cargo ships have put into Crimean ports in violation of EU sanctions.

“I don’t know how many ships of Turkish origin have done this,” he said. “Turkey maintains that every time it is done, they are charged. I am skeptical and would be of any claim that this is not done with tolerance, if not endorsement.”

Better maritime monitoring would help, he said. “Something that needs to be done is improve intelligence sharing in [the Romanian city of] Constanta. Ukraine and Georgia see everything there. If you could establish a common shared maritime picture of the Black Sea and what’s going in and out, that would help in identifying ships bringing commerce into Crimea when it's not supposed to.”

But it won’t solve everything. The Russian Navy has shown a willingness to mount electronic attacks on ships in the region.

Russia’s additional military muscle also will help Moscow shape the economic futures of Black Sea nations, Hodges said, including NATO member Romania and NATO-aspirant Georgia. China’s One Belt, One Road Initiative is expanding toward the Black Sea, which could become an important “portal between Eurasia and Europe,” he said. “Georgia becomes the portal on the east end and Romania becomes the portal on the west end of the Black Sea. With rail infrastructure, a whole lot of markets become accessible out of Eurasia.”

The Future of Crimea

Since 2014, the U.S. government has treated Russia’s occupation of Crimea as an illegal annexation. State Department Special Representative Kurt Volker recently described the situation as an “occupation.”

President Donald Trump long has been softer on the issue. In 2016, Trump told ABC News' George Stephanopoulos, “Putin would not to go into Ukraine, all right? You can mark it down and you can put it down.” After Stephanopoulos pointed out that Russia was already in Crimea, Trump offered a line of reasoning that has become a Kremlin talking point: “You know, the people of Crimea, from what I've heard, would rather be with Russia than where they were.”

Since then, various people in his orbit have tried to sell the president on a peace plan that would recognize Russia’s annexation of the Crimean Peninsula. Former Trump lawyer and current federal prison inmate Michael Cohen, along with Trump business associate Felix Sater, discussed such a plan with aspiring Ukrainian politician Andrii V. Artemenko in 2016. Artemenko said that the proposal had Putin’s backing. It reportedly made it as far as former National Security Advisor Michael Flynn’s desk before he was fired after lying to the FBI about his conversations with the Russian ambassador.

At the State Department, Russia’s current military buildup on Crimea doesn’t alter their policy position, yet.

“The United States does not and will not recognize Crimea’s claim to annexation by Russia,” Volker said during a May press event. “We have put in place under Secretary [Mike] Pompeo a long-term policy of refusing to recognize this, and we have sanctions in place as a result, and that’s not going to change.”

But the buildup diminishes any prospect of the United States evicting the Russians from the peninsula by force. “It would be very, very challenging from a military standpoint,” Hodges said.

The result appears to be an intractable standoff.

“We must never officially acknowledge and not tolerate” Russia’s illegal presence, Hodges said. “I’m not optimistic that there will be a resolution any time soon.”

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