The NATO question

The introduction of Russian defense forces into the Syrian conflict has proven a controversial subject for the international community, with reports that Moscow's first airstrikes in the country targeted US-trained rebels and resulted in more than 30 civilian deaths.

However, Russia's latest incursion into Turkish airspace has raised the stakes of an already fractioned conflict, prompting Turkish President Recep Tayyip Erdogan to state, "If Russia loses a friend like Turkey, it will lose a lot."

Between NATO and Russia

Hall Gardner, professor of international politics at the American University of Paris, told DW that Russia's latest maneuvers are not an unfamiliar sight, although they are "problematic."

"The Russian intrusion into Turkish airspace - and in the airspace of other NATO members as well as states considering NATO membership such as Sweden and Finland over the past several years - is very problematic. Moscow has justified these 'encounters' on the basis that the number of fighters in the NATO Baltic air-policing mission has been increased since March 2014," Gardner said.

In 2015, Russia's violations of Baltic and Nordic states' airspace prompted a diplomatic row with Estonia, and even caused Sweden to reconsider NATO membership.

However, this is not the first time Turkey has rebuked Russia over its actions in neighboring Syria. On Friday, Turkey - along with key members of the US-led coalition against "Islamic State" extremists - called on Russia to stop targeting rebels backed by the coalition.

"Ankara is caught between a rock and a hard place. Unlike the Europeans and other NATO countries, Turkey did not engage in economic sanctions against Moscow in the aftermath of the Russian annexation of Crimea," Gardner noted.

"At the same time, as a NATO member, and due to its geographic position, Turkey cannot ignore Moscow's threatened military build-up in Crimea, plus Russian efforts to dominate the northern regions of the Black Sea," Gardner said.

Testing resolve

NATO Secretary General Jens Stoltenberg on Monday criticized Russia's violation of Turkey's airspace, urging Moscow to "avoid escalating tensions."

"Russia's actions are not contributing to the security and stability of the region. I call on Russia to respect NATO airspace, and to avoid escalating tensions with the alliance. I urge Russia to take the necessary steps to align its efforts with those of the international community in the fight against ISIL," Stoltenberg said, refering to "Islamic State."

However, the statement was slammed by Permanent Representative of the Russian Federation to NATO, Alexander Grushko, who claimed that "Russian clarifications were ignored."

"Such incidents are subject to clarifications through bilateral and military channels. It is a well-established practice. The fact the Russian clarifications were ignored reveals genuine intentions of NATO Council organizers," Grushko said in a statement provided to DW by the Russian mission to NATO.

"But this is a genre of the information war," Grushko added, evoking a buzz phrase used by Russian officials to characterize an alleged smear campaign by international media.

'A deadly game'

Russia's incursion into Turkish airspace - an apparent consequence of the airstrikes in Syria - has raised the question of Russian President Vladimir Putin's intentions outside his country's borders, especially as Moscow has been accused of backing rebels in the eastern Ukrainian conflict.

Andrew Michta, professor of national security affairs at the US Naval War College, told DW that Moscow's latest moves in Turkey are meant to bolster Russia's sphere of influence by testing NATO's resolve, a similar maneuver used by Moscow in the Nordic and Baltic regions.

"Putin's overarching goal is to re-establish a sphere of privileged interest along Russia's periphery," Michta said.

"With their incursion into Turkey, Russia is testing NATO's resolve and response time, and communicating that they are not afraid to escalate," Michta noted, adding that Moscow's military exercises in the Baltic and Nordic regions serve the same purpose.

"Putin is playing a deadly game to bring Russia back as a major global power, leveraging the current fatigue and disarray in the West…This has raised the risk of miscalculation and war in Europe to a degree unknown in the continent since the end of the Cold War."