A cease-fire brokered by the United States and Russia, in consultation with Jordan, began in southwest Syria two weeks ago, including along the sensitive border between Israel and Syria, following a meeting between US President Donald Trump and Russian President Vladimir Putin at the G20 summit in Germany.As is customary, Trump took to Twitter to praise the agreement: “Now it is time to move forward in working constructively with Russia!” he wrote in a post. Not everyone, however, welcomes the deal and for good reason.The agreement fails to address the active threat of Iran, ignoring the realities on the ground in Syria, where after taking over Iraq, the world’s leading state sponsor of terrorism seeks to ensure its dominance through Hezbollah, other Shi’ite militias and its influence over Syrian President Bashar Assad himself.Israel has long warned about the strong footprint left by the Iranians in Syria and neighboring Iraq. Prime Minister Benjamin Netanyahu predicted that the deal would pose a long-term threat on Israel’s northern border by cementing Tehran’s presence there. Iran wants Assad to retake all of Syria and, by extension, consolidate its own power.And accepting the terms of the agreement doesn’t fit into that scheme.Already the Iranian presence on Israel’s border is impossible to miss. Just meters from the fence that separates Israel and Lebanon near Metulla, flags adorned with Iranian, Hezbollah and Palestinian symbols are provocatively displayed on the Lebanese side of the border. The message is clear. Iran is looking down on Israel from the north.Meanwhile, forces loyal to the regime in Tehran are closing in on Israel from inside Syria. The Iran-backed Hashd al-Shaabi militia has reached a strategic corridor along the Iraq-Syrian border near Sinjar and with the Syrian regime simultaneously advancing along the other side of the fence near al-Tanf, the two Iran-backed parties could physically link the territory. In effect, that would allow the Iranians to create a corridor between Iran and Lebanon, through northern Iraq and Syria. The establishment of a permanent Iranian base in Syria poses a direct and imminent threat to Israel, placing it at risk of a simultaneous confrontation with Tehran’s proxy Hezbollah in Lebanon and Iranian-backed militia groups in Syria.Iran’s terrorist activities along the border have long caused headaches in Jerusalem. In 2015, several high-ranking Hezbollah and Iranian operatives were killed in a strike on a convoy in Syria, near the border with Israel, including notorious Hezbollah commander Imad Mughniyeh and IRGC commander Mohamed Allahdadi.Crucially, the US could help Israel contain the threat, as it is in a position in Syria it hasn’t been in a long time. It has leverage.Following the decision by the Trump administration early in the presidency to enforce the red line declared but never enforced by president Barack Obama, the US won back some of the credibility it had squandered over eight years.Responding to what President Trump called a “horrible chemical weapons attack” in Idlib, the US military delivered powerful air-strikes on a Syrian airfield, in the first direct military action against the Assad regime.With the lightest application of force, the US netted meaningful leverage – much like the limited application of military power by Russia had given it absolute primacy in shaping the battlefield and the future of the territory.Although the decision didn’t translate into significant military intervention or a major overhaul of US policy in Syria, the strikes were applauded by the opposition and crucial in signaling to Assad and his allies, Russia in particular, that the US was back in the game and that our interests need to be taken into account.Of course, a cease-fire that stops or reduces the bloodshed is, in theory, always a good thing. But not if it’s being exploited by forces not aligned with our interests, like Hezbollah and their terror-masters in Tehran, with the potential to unleash even more death and destruction against our allies, and likely to create a major conflagration in an already unstable region. Unfortunately, prior experience in Lebanon, Iraq and elsewhere teaches us that the cease-fire will be exploited by these maligned actors, and others.Not only does the deal require blind faith that the Russians will hold their Syrian partners accountable in the event of a violation. Given the length to which Russia protects Assad amid chemical weapons attacks on innocents and untold other brutality, that is highly unlikely.This troublesome development is not helped by the fact that the Trump administration last week announced the end to the CIA’s covert program to arm and train moderate Syrian rebels battling Syrian regime forces. It is a move long sought by Russia that will further tip the balance in favor of Assad and the Russian-Iranian-Hezbollah axis.Until now, reports of a substantial US-Russia realignment were largely exaggerated. But the brokered ceasefire and the phasing out of the covert CIA program clearly reflect the administration’s intent to find ways to work with Russia even if it makes the US and its allies less safe.It is an incredibly short-sighted and dangerous policy that tragically throws away the hard-won goodwill garnered by the administration from opposition figures inside Syria and allied governments in the Middle East.For Syria, it marks yet another missed opportunity in a long line of mistakes.The author is CEO and president of The Israel Project.