The United States said this weekend it would withdraw Patriot air defense systems from Turkey, supposedly because the batteries are needed elsewhere to defend against threats from Iran and North Korea.

This official explanation, as reported by The New York Times, is difficult to believe, especially when a statement from the United States embassy in Ankara said the missiles were sent back for “critical modernization upgrades.”

Which is it? Are the systems in need of an upgrade? Or are they needed elsewhere?

Puzzling

Patriots from Turkey’s NATO allies Germany, the Netherlands and the United States were deployed to the country’s southern border in 2012 after a Turkish jet was shot down by Syrian air defenses. The Spanish took over from the Dutch earlier this year while the Germans have said they will pull out in 2016.

The systems have not been called on to intercept a single missile and their deployment was seen more as a reassurance of Western countries’ commitment to Turkey’s security than anything else.

Which makes their removal all the more puzzling.

The Americans have more than 1,000 launchers in service. What sudden threats have emerged from Iran or North Korea that they could not afford to station a mere two on the Syrian frontier when the Turkish government considers them a vital tripwire to dissuade aggression?

Timing

The timing of the removal may offer a clue.

Last month, Turkey joined the international air war against Islamic State militants in Iraq and Syria. It simultaneously launched an anti-terror campaign against Kurdistan Workers’ Party (PKK) militants at home and affiliated Kurdish separatist groups in northern Syria.

Turkey’s stated objective is to create a “safe zone” on its border, north of the Syrian city Aleppo, where refugees could be housed. The proposed safe zone conveniently overlaps with the only part of the frontier that is not controlled by Kurdish militias. Rather, it is in the hands of the self-declared Islamic State.

Western countries welcome Turkey’s belated support for the war against the Islamic State. But they are wary of its anti-Kurdish actions, especially when the Kurds are among the most effective fighters in keeping the caliphate at bay.

America is reluctant to pick sides. But with its own forces on the border, it risks getting involved. Imagine if Kurdish fighters in Syria fired a rocket at Turkey and one of America’s Patriot batteries intercepted it. It would be difficult for the Americans to maintain then that they are neutral in Turkey’s war on the Kurds.

Russia

The Policy Tensor raises another possibility, arguing that the real reason the Patriots were deployed in the first place was to dissuade intervention by Russia on the side of Syrian president Bashar al-Assad:

Turkey has always played the role assignment to it by geography, sitting as it does under the belly of the bear. For instance, the Cuban Missile Crisis was resolved by a secret American offer to withdraw Jupiter missiles from Turkey.

The withdrawal could have been part of a secret deal with Russia, The Policy Tensor argues, which would suggest an international effort to resolve the Syrian conflict, now in its fifth year, is underway.

We’ll see.