Russian fighter jets and bombers parked at Khmeimim air base in Syria on June 18. (Vadim Savitsky/ AP)

Russia ratified a treaty with Syria on Friday that gives Moscow its first permanent air base in the Middle East, a symbol of the Kremlin's desire to project strength overseas, as Russian officials considered renewing other Soviet-era bases in Cuba and Vietnam.

Friday's developments were largely symbolic: With the onslaught of Russian airstrikes in Syria, Moscow has left no doubt about its commitment to the regime of President Bashar al-Assad; there's no clear evidence that Cuba or Vietnam would be open to the return of the Russian military.

But it's clear that Moscow is acting on bringing to life President Vladimir Putin's vision of Russia as a global military power at a time when tensions between Moscow and Washington are as high as they've been since the Cold War.

Secretary of State John F. Kerry called Friday for the Syrian and Russian governments to face a war-crimes investigation over attacks on civilians in Syria. Moscow has rejected accusations that its airstrikes are targeting civilians and insists that its goal in Syria is to assist Assad in the fight against terrorism.

Russia warned Thursday that its advanced air defenses in Syria would be ready to fight off a U.S. strike against the Syrian army, and the newspaper Kommersant quoted a military source Friday as saying Russian forces have authorization to “shoot to kill”  if they come under attack.

The broad, open-ended agreement ratified by the Russian parliament Friday allows the Kremlin to indefinitely maintain a military deployment in Syria “aimed at maintaining peace and stability in the region.” The contract can be terminated by Russia or Syria with one year’s notice and went into effect Aug. 26, 2015, the day it was signed.

Putin submitted it to the Russian parliament for ratification in August of this year, and the government has not given an official reason for the delay. The Russia-Syria treaty was unexpectedly published on the government's clearinghouse for official documents in January, allowing our colleague Michael Birnbaum to translate and break down the agreement.

“Russian military personnel and shipments can pass in and out of Syria at will and aren’t subject to controls by Syrian authorities,” the document says. “Syrians can’t enter Russian bases without Russia’s permission. And Russia disclaims any responsibility for damage caused by its activities inside Syria.”

Additionally, according to the agreement, Russia receives use of the Khmeimim aviation base with no fee and does not have to pay taxes in Syria.

Kommersant reported Friday that military officials are considering deploying Su-25 ground-attack aircraft at Khmeimim that Putin ordered out of Syria in March, saying that the Russian military had fulfilled its mission. The newspaper, quoting a “high-ranking military source,” said that two guided-missile ships would join the Russian naval task force in the Mediterranean Sea, to be bolstered later also by a strike force led by the aircraft carrier Admiral Kuznetsov, which that will set off for Syria later this month.

With the Russian military presence in Syria formalized, a lawmaker asked a senior defense official about the bases in Vietnam and Cuba, closed in the early 2000s.

Deputy Defense Minister Nikolai Pankov said the military is “reviewing” the decision to close the Lourdes signals intelligence base in Cuba and the deepwater Cam Ranh naval base in Vietnam, but did not offer specifics, according to Russian news agencies. “As for our presence on faraway outposts, we are working on this,” Pankov said.

Putin's spokesman, Dmitry Peskov, also declined Friday to give specifics about a possible return to Cuba and Vietnam, saying only that the global situation requires Russia to consider possible responses.

Putin has openly criticized the United States for failing to reciprocate on Russia's drawdown of its Soviet-era military reach. Russia’s annexation of Crimea and its entry into the war in Syria have underscored Moscow’s newly assertive foreign policy.

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