The first serious schism in the Trump-Israel relationship emerged last week with the president’s decision to pull US troops out of Syria over the strong objections of Prime Minister Benjamin Netanyahu. In what has been described as a “tense” phone call, the Israeli leader reportedly explained that it would be seen as a strategic setback for the United States and increased danger for Israel.The importance of an American presence was bolstered by several events last week. The presidents of Russia, Iran and Turkey met in Ankara to discuss the future of Syria and carve out their spheres of influence. The United States was pointedly excluded.The second event was the latest Syrian poison gas attack on its own citizens, killing at least 50 and wounding hundreds of civilians in a rebel-held suburb of Damascus. Russia, Syria’s protector, denied there had been a gas attack, but don’t forget Russian President Vladimir Putin has no qualms about using chemical weapons – just ask Sergei Skripal and his daughter. Iran also denied there was a gas attack, saying the accusations were just “an excuse to take action.”Both denounced an Israel attack early Monday on a major Syrian airbase, T-4, the likely spot from which the chemical attacks were launched. It is used by the Iranian Revolutionary Guard Corps for housing senior personnel, strategic weaponry and sophisticated drones, and supplying weapons for Hezbollah. Iran reported seven Revolutionary Guards were killed and about 40 wounded.No Russian personnel or aircraft at the base were reported targeted or harmed.As the Americans prepare to march out of Syria, Iran’s military footprint is spreading to include 10 military bases, more than 40 permanent military positions across the country and over 120,000 fighters, including Shi’ite militias and non-Syrians, according to the Daily Beast.Without an American presence in Syria to help contain the Assad regime and its Shi’ite allies, Israel may feel compelled to increase the level and lethality of its unilateral actions to protect its borders.Israel is not looking for war with Iran, but the same cannot be said with any level of confidence about Iran and Syria.President Barack Obama drew a red line threatening military action if Syrian President Bashar Assad used chemical weapons, but when that did happen in 2013, he backed down at the urging of Putin, who brokered a deal under which Assad promised to surrender all his chemical weapons.After denying he even had chemical weapons, Assad finally admitted he did but insisted they weren’t for use against his own people, only Israelis. Obviously he held some back.Obama’s deal with Putin worried Israelis, who understood that the president’s threat to use force to prevent Iran from getting a nuclear weapon could not be taken seriously. Today, Israel has new reason to question American resolve.With Trump anxious to retreat, Israel feels increasingly isolated as its greatest enemy, Iran, is on its doorstep and digging in for the long haul.Netanyahu can’t marshal his friends on Capitol Hill this time to pressure a president to change his mind. The Republican Congress was anxious to pick a fight with a Democratic president, but not with one of their own.Israeli officials think Trump is being myopic, focusing on the defeat of Islamic State and ignoring the critical mission of preventing Iranian entrenchment in Syria, which it is already using as a base to train, arm and supply Israel’s enemies in Syria, Hezbollah, Hamas and Shi’ite militias.Iran reportedly may even build a nuclear reactor in Syria; Israel destroyed a previous one, built by North Korea, but this time it could likely have heavy protection from Iranian and Russian air defenses.Trump’s withdrawal is a green light for Putin, Assad and the ayatollahs, and a strategic crisis for Israel.If Trump keeps his vow to tear up the Iranian nuclear agreement next month, Iran may further increase its military profile along Israel’s borders.Sen. John McCain, a fellow Republican, suggested that Trump’s announcement of an early troop withdrawal from Syria may have emboldened Assad and prompted his poison gas attack last weekend.The US has some 12,000 forces in northern Syria working with the Kurdish-led opposition. They’ve been effective in wiping out remnants of ISIS but the job is far from finished.Netanyahu worries that Trump’s hasty retreat is already being seen as a major victory for Syria, Russia, Iran and allied Shi’ite militias like Hezbollah.Many of senior officials at the Pentagon, CIA and State Department advised Trump against leaving a power vacuum that Iran and Russia will quickly fill, if they haven’t already. What’s more, they caution, ISIS could still rebuild with the US-led coalition gone.Trump wasn’t listening. “I want to get out. I want to bring our troops back home,” he insisted. He wants to be able to go voters this fall to declare ISIS “almost completely destroyed” and that he has brought his victorious forces home.That will mean scrapping long-planned US operations to clear land mines, restore basic services like water and electricity and foster political stability. “I want to start building our nation,” the isolationist Trump explained, leaving the Saudis and others to handle the mopping up.That has Israel very worried. The reality is the US began its withdrawal during the Obama administration with its reluctance to get very involved in the Syrian civil war, and Trump, though he would harshly deny it, is continuing that policy.It constitutes a serious strategic setback for American leadership and Israeli security. Leaders of the Jewish state can’t help worrying whether Washington will have its back it if it decides on a preemptive strike against a Syrian- based Iranian threat.Trump’s new national security advisor, John Bolton, just started work and unlike the isolationist president, he’s an interventionist. He also has many friends in Israel, particularly in the ruling coalition, and they’re hoping and urging him to persuade Trump to change is mind.For now, the US does not have a policy to contain and deter Iran. Trump’s planned retreat is a victory for Russia and Iran, and a direct threat to Israel.