The clash over the weekend between Israel and Syrian and Iranian forces signals a new chapter in the ongoing realignment of powers in the Middle East.Yet, while Russia, Turkey and Iran continue to assert themselves in the region and constitute a loose axis of powers, America is sorely missing from the geopolitical equation.Last month at Stanford University, US Secretary of State Rex Tillerson outlined a new Syria policy, which at least ostensibly posits expansion of US goals in Syria beyond the fight against Islamic State.Tillerson talked of keeping a military force in Syria not only to fight IS and al-Qaida affiliated terrorists, but also to counter Iran’s pernicious influence.He also suggested the US would expand its military presence in Syria to include the establishment of a 30,000-strong border security force in northern Syria together with the US’s allies the Kurds.However, words have so far not been matched with action.Just days after Tillerson’s speech, Turkey intensified its offensive against US-aligned Kurdish forces in northern Syria. Turkish forces backed by warplanes and artillery captured territories previous controlled by Kurdish forces, while Washington stood by doing nothing.The turning of backs to the Syrian Kurds, a group that did more than any other to fight IS, is a harbinger of what the US reaction might be should Israel get dragged into a direct conflict with Hezbollah, Syria, Iran and perhaps even Russia.If the Trump administration has no qualms about watching Turkey use US-supplied F-16s against supposed American allies in northern Syria, what does that say about US declarations to support Israel’s right to defend itself? US inaction to protect the Kurds has more far-reaching ramifications as well. It indirectly strengthens Russia and Iran by adding Turkey to the list of nations that are openly defiant of the US. It undermines NATO, an organization set up to counter Russia, by giving Turkey, a NATO member, full rein to advance Russian interests.Prime Minister Benjamin Netanyahu has devoted much time and energy to improving Israel’s relations with Russia.And the two countries do have common interests. Militarily, Israel is a stabilizing element in the region. Israel shares intelligence with Russia. And cultural ties between the two countries are strong due to Israel’s large Russian population.But Russia under the leadership of President Vladimir Putin has its own set of concerns. It has invested both blood and treasure in propping up the Assad regime as a means of defending its Syrian-based naval base and military assets.Iran was an important ally in this endeavor. If Russia were pushed to choose between Iran and Israel, it is not at all clear that Moscow would side with Jerusalem over Tehran.US support is therefore critical if Israel is to continue to enjoy freedom to act militarily against Iran if necessary, even when such action is opposed by Russia.Yet, Tillerson has been remarkably silent in the wake of Israel’s recent escalation with Syria and Iran. He has not so far confirmed that he will reroute his current visit to the Middle East to include a stop in Israel. His not planning to visit Israel in the first place is a testament to his disengaged style.Contrast Tillerson’s non-involvement to the heavy involvement during the 2006 Second Lebanon War of then-US secretary of state Condoleezza Rice. Rice was intimately involved in every stage of the unfolding conflict and was instrumental in bringing about its resolution.The problems with US policy on Syria did not start with Tillerson. When Barack Obama let his red lines be violated without a response, it showed the world that the US was not serious in solving the crisis in Syria.It’s not too late though for Tillerson to change course.Despite Russia’s heavy involvement in the region, the US remains the world’s most powerful nation, backed by the world’s biggest, most dynamic economy. Only the US has the ability to defuse the situation in Syria by taking steps such as forcing Turkey to stop its attacks on the Kurds and by putting pressure on Iran to keep clear of Israel’s borders.By failing to act, America emboldens Iran and increases the likelihood of war.