Slowly but surely, a strategic reorientation is underway in Israel. Earlier this month, Prime Minister Benjamin Netanyahu made a high-profile state visit to Russia. The trip, Netanyahu’s fourth in the past year, was a public sign of the rapidly expanding ties between Jerusalem and Moscow.For Israel, the unfolding strategic alignment with Moscow is driven by both domestic and international considerations. At home, ethnic Russians have become an increasingly potent – and vocal – force. Now approaching a quarter of the country’s total population of eight million, this constituency (and its most prominent political party, Yisrael Beytenu) has emerged as something of a kingmaker in national politics. Prime Minister Netanyahu’s recent decision to elevate Yisrael Beytenu’s leader, Avigdor Liberman, to the post of defense minister in a bid to strengthen his fragile political coalition was simply a sober recognition of this fact.Abroad, meanwhile, years of neglect from, and acrimonious relations with, the Obama White House has the country’s leadership openly questioning the durability of US-Israeli ties. For, while there indeed remains a large, bipartisan reservoir of support for Israel in the US Congress, the chilly nature of personal ties between Netanyahu and President Barack Obama has caused unmistakable turbulence in the once “unshakable” US-Israeli relationship. Uncertainty over who the next occupant of the White House might be, meanwhile, has prevented Israeli policymakers from assuming that the current discord is simply a passing phase.At first blush, Russia seems like a viable alternative. In recent years, under the direction of its strongman president, Vladimir Putin, Moscow has moved back into the Middle East with a vengeance. It has deftly exploited the vacuum left by the Obama administration’s disengagement from the region, expanding its political and economic ties throughout the Middle East and North Africa. And Israel, energy-rich and economically dynamic, has become as an important strategic prize for the Kremlin, leading to quickening political contacts over the past year – and the promise of still more to come.But, as attractive as the idea of an alignment with Moscow might be, there are at least three reasons for Israeli policymakers to remain deeply apprehensive of Russia.Iran – Over the past decade, Russia has served as a key strategic partner of the Iranian regime, and a major enabler of its nuclear effort. With the start of negotiations between Iran and the P5+1 powers in November of 2013, the Kremlin took on an even more decisive diplomatic role, and was instrumental in securing a settlement highly favorable to the Iranian regime.Moscow has unquestionably reaped the dividends. Since the passage of the Joint Comprehensive Plan of Action last summer, Russia has signed new, multi-billion dollar arms deals with Tehran – greatly strengthening Iran’s military potential, as well as the threat it poses to its neighbors, in the process.Syria – Russia’s decision last fall to intervene militarily in support of Syrian president Bashar Assad touched off a flurry of diplomatic activity in Israel. Prime Minister Netanyahu promptly flew to Moscow to liaise with President Putin to receive security assurances, and the militaries of both countries remain in close contact in order to “deconflict” the airspace in southern Syria.This modus vivendi has worked well, at least so far. But Russia’s strategy is shifting; back in March, Putin – worried over the possibility of an open-ended conflict in the Middle East – unexpectedly announced that his government was withdrawing the “main part” of its forces from the Syrian battlefield. Since then, the Kremlin has adopted an increasingly minimalist approach. Instead of pursuing an expansive campaign to dislodge the Islamic State terrorist group from the country, Russia’s “Plan B” involves the creation of an Alawite enclave in the country’s west, encompassing its strategic naval presence in Tartus and its newly-erected air base in Latakia.That, however, effectively leaves Israel’s northern flank undefended, and raises the possibility of far greater instability along the common border between the two countries.America – Moscow’s enduring objective in the Middle East is to become an indispensable power broker, and to do so at America’s expense. That goal is likely to make it exceedingly difficult for Israel to reconcile its burgeoning ties with Moscow with its historic ones to Washington.Netanyahu has been quick to stress that America, and not Russia, remains Israel’s main international partner. But while the Israeli government may not see its relationship with Russia as a zero-sum game, the Kremlin clearly does. It is reasonable to expect, therefore, that Moscow’s outreach will be accompanied by initiatives intended to drive a wedge between Jerusalem and Washington. The likely price of Russia’s friendship, in other words, will be a worsening of the US-Israeli partnership.All of which should serve to remind of us of the old adage that countries do not have eternal allies, only eternal interests. Just because Russia’s temporarily coincide with those of Israel doesn’t mean that Moscow represents a dependable ally for Jerusalem.The author is vice president of the American Foreign Policy Council in Washington, DC.