Abdalghne Karoof / Reuters A Free Syrian Army fighter wearing a gas mask, carries his weapons as he walks past a damaged tank, after seizing a government military camp used by forces loyal to Syria's President Bashar al-Assad, near Idlib, June 13, 2013.

52 days after an Israeli general publicly declared that Syria has used chemical weapons against rebels, the Obama administration reached the same conclusion, and used the finding to justify announcing it would send small arms to the side of the victims. “I will not say ‘We told you so,’ only, okay, the proof is there, so there’s no more question about it,” says Israeli foreign ministry spokesman Yigal Palmor, taking with a smile the easy part of the equation now laid before Israel. As for the hard part: “Now, what should be done? It’s not for Israel to say, because the international involvement in this should not include Israel. Israel follows very closely developments there. It’s very concerned about activity on its borders. But we’re not aspiring to be involved in any action about what’s happening in Syria.”

In fact, of course, Israel is closely involved already, and in more ways than they are acknowledged publicly. Israeli military officials tell TIME that American intelligence had the same information that Brig. Gen. Itai Brun cited in his April 23 presentation to a public conference – video footage showing victims foaming at the mouth, and other indicators that made it clear that sarin had been used on the battlefield more than once. “We are sharing,” one Israeli intelligence official said at the time. “We have our cards on the table with the Americans for a long time. They’ve had all this information.”

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Though the speech embarrassed President Obama, who had repeatedly called use of chemical weapons “a game changer” in his Syria policy, it was officially inadvertent. No one in Israel’s political echelon knew of Brun’s remarks in advance, and officials from both countries spent several days publicly repairing the impression that Israel was trying to force Obama to intervene. At an operational level, cooperation between the two countries has been exceptionally close — and growing closer as Washington publicly ramps up its military involvement in the Syrian conflict.

“Things are happening behind the scenes,” says one Israeli official. “Things are really happening.”

Earlier this month, the Pentagon announced it was sending F-16s and Patriot missile batteries to Jordan, ostensibly for an exercise (“Eager Lion”), but which would remain in the Hashemite Kingdom afterward.

“It’s a clear, purposeful, presence of a strike force near the border of Syria,” the Israeli official noted. “I think it’s a message, a clear message.” The message is also meant to be legible to Iran, which is arming Syria and the Lebanese militia Hizballah by air, as well as testing the resolve of Western powers who threaten to strike its nuclear program. “It’s only a short leap to the Gulf,” the official said.

Patriot batteries went into Turkey last year, under the banner of NATO. And the chief of Mossad, Israel’s overseas intelligence agency, traveled to Ankara this week to meet with Turkey’s National Intelligence Organization, known by its Turkish initials MIT. As opponents of Syrian President Bashar Assad organize themselves to assist the rebels opposing him, Israel feels obliged to lay low. Though closely aligned with Washington, and maintaining diplomatic relations with Jerusalem, countries like Jordan and Turkey have majority Muslim populations who would not welcome overt military cooperation with Israel. “If this is to hold water, this cannot involve Israel,” the Israeli official said.

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Behind the scenes, however, Israeli and U.S. military officials are coordinating how to target and destroy Assad’s arsenal of unconventional weapons under assorted scenarios, Israeli military and intelligence officials tell TIME. One scenario would be the sudden removal of Assad from the scene, be it by flight, death or if he simply disappears. That would prompt the allies to launch operations on the estimated 18 depots and other sites where WMDs are stored, the officials said. Search and destroy operations would also be launched if the weapons appeared to be about to fall into the hands of the rebels, which include Islamist extremists aligned with al-Qaeda.

The Israeli officials emphasized that it had not been decided whether both Israeli and U.S. forces would act, or who would do what. But the U.S. plans called for deploying forces on the ground as well as waves of airstrikes, to assure that the chemical and biological components are neutralized, according to the Israeli officials.

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Israel already has struck by air inside Syria three times this year, targeting advanced weapons systems such as anti-aircraft batteries and highly accurate Russian-made missiles that officials said were being transferred to Hizballah, something Israeli officials repeatedly had warned would prompt discreet, surgical action intended only to safeguard its military advantage over the Lebanese militia, which is sponsored by Iran and supported by Syria (where Hizballah recently sent troops to help Assad).

“The main arms of concern to us are the arms that are already in Syria — these are anti-aircraft weapons, these are chemical weapons and other very, very dangerous weapons that could be game changers,” Israeli Prime Minister Benjamin Netanyahu told the BBC in April, in remarks the Israeli foreign ministry said remained operative in the wake of Obama’s decision to arm the rebels. “They will change the conditions, the balance of power in the Middle East. They could present a terrorist threat on a worldwide scale. It is definitely our interest to defend ourselves, but we also think it is in the interest of other countries.”

Aaron J. Klein contributed reporting from Tel Aviv

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