Russia is upping the ante in the Eastern Mediterranean in response to the downing of its fighter jet by Turkish F-16s last week. Russian President Vladimir Putin has deployed S-400 air-defense missiles in Syria and expanded fighter escorts for bombing operations. While Moscow has predicated its intervention in Syria on supporting the Bashar al-Assad regime’s fight against “terrorism,” the expansion of air defenses indicates that Putin’s plan goes far beyond fighting Syrian rebels and the Islamic State (ISIS), or even deterring Turkish aggression. Instead, he is looking to strong-arm the U.S. and NATO out of an area he sees as Russia’s domain.

The S-400 Triumf, known by NATO as the SA-21 Growler, is Russia’s most advanced air-defense system in operation. Equipped with sophisticated radars and missiles, the Triumf can detect and strike airborne targets as far as 250 miles away. With its deployment, Russia extends its surface-to-air missile coverage nearly 200 miles farther than the S-300F system aboard the guided-missile cruiser Moskva already stationed off the Syrian coast.

When Moscow first deployed forces to Syria in September, it sent SA-15 and SA-22 short-range air-defense systems, along with a naval task force (which included the Moskva), to guard Russian installations along the coast in Tartus and Latakia provinces – incidentally home to Assad’s Alawite power base. Those systems are believed to still be stationed in the country, with the Moskva now deployed closer to the coast of Turkey in response to last week’s downing of the Russian jet. With the S-400s, Russia’s ground-based defenses can now cover nearly all of Syrian airspace except for the northeast corner, while also extending into parts of southern Turkey and Cyprus where U.S., British, French, and Turkish warplanes are based.

The earlier systems provided more than adequate layers of defense for Russian forces. The addition of the S-400s escalates tensions in the skies over Syria by projecting Russian power beyond regime frontlines and into key areas of central Syria where the anti-ISIS coalition operates. As the commander of U.S. Air Force Central Command said understatedly, the S-400s “complicate things.”

Although Pentagon officials insist the S-400s will not alter the coalition’s ability to do its job, the Russians have also instituted another measure aimed at forcing the U.S. and its allies to operate with increased caution when encountering Russian aircraft. Alarmingly, the Kremlin has ordered Su-30 and Su-27 fighters to begin escorting all Russian strike aircraft flying over Syria. This will put coalition and Russian aircraft in close proximity, increasingly the likelihood of flashpoints. According to Russian Defense Minister Sergei Shoigu, the fighters’ rules of engagement will be exceedingly permissive, as they will be authorized to “destroy any aerial target posing a potential danger to our aircraft.” These extensions of Russian anti-air assets may already be affecting coalition operations, as strikes declined in the days following Moscow’s announcement with no bombs being dropped west of the Euphrates.

Turkey’s downing of the Russian aircraft accelerated Putin’s moves in Syria, but undermining the American-led coalition appears to have already been the goal. Moscow has bombed U.S.-backed rebel groups, and is refusing to work with the U.S.-led anti-ISIS coalition. On October 7, Russia unleashed a barrage of cruise missiles without warning from the Caspian Sea through coalition-patrolled airspace in Iraq. Since neither ISIS nor other Syrian rebels have any serious air-defense systems inhibiting Russian aircraft from flying throughout Syria, it’s hard to view this as anything other than a Russian provocation.

Russia also appears determined to minimize the U.S.-led efforts in Syria. Putin’s defense ministry has released regular reports on the number of strike sorties and aircraft it is flying in Syria. The numbers are almost always far higher than the U.S.-led strikes (though these statistics are hard to compare, as sortie numbers and strike numbers are not the same). Regardless of their accuracy, they are meant to reinforce the impression that the U.S., with all its advanced military capability, has been feckless against ISIS.

The S-400s now give Russia a tangible edge. They can block any further direct foreign intervention in Syria. Moreover, they contribute significantly to Moscow’s efforts to reassert its military might as a counterbalance to American power after years of post-Soviet decline. Using hard power, Putin is gaining increased leverage over the U.S. and its allies in Syria, forcing them to accept Russia’s presence, which will ultimately weaken efforts to destroy the Islamic State, not to mention the policy of hastening the exit of the Assad regime.

Patrick Megahan is a research analyst at Foundation for Defense of Democracies focusing on military affairs. He manages the website MilitaryEdge.org.