Benjamin Netanyahu had not been planning to attend the climate conference in Paris - environmental protection and global warming is not high on the Israeli prime minister's agenda.
That changed, however, in the wave of the Paris terror attacks last month. And while most of the attention surrounding his short visit to the French capital was focused on his chance encounter and handshake with Palestinian President Mahmoud Abbas, whom he had not met in five years, the most significant of his meetings in Paris was with Russian President Vladimir Putin.
While most of the discussions between world leaders at the summit were conducted standing and at the margins of the conference, Mr Netanyahu and Mr Putin had a full, sit-down meeting.
They met only two months ago in Moscow, but both men had a clear message to send out in their post-meeting statements: Israel and Russia are closely co-ordinating over the situation in Syria and the military channel between them is working fine.
Meanwhile, Israel is also closely co-operating with its more traditional American and European allies, with whom it has been exchanging intelligence on Daesh.
In the chaos of Syria, Israel is happy to see Russia usurp Iran as main power
Last week, during the height of the terror alert in Brussels, IDF chief of staff Lieutenant General Gadi Eizenkot flew to Belgium where he met his Nato counterparts including Supreme Allied Commander of Europe General Philip Breedlove.
The Israelis and Russians have been eager to contrast their successful co-ordination with the increasing tension between Russia and Turkey. The shooting down of a Russian bomber by Turkish F-16s last week has escalated into a full-blown diplomatic crisis.
In the past few days, senior Israeli officials have been talking quite openly about the Israeli-Russian military relationship.
Over the weekend, both ex-Major General Amos Gilad, head of the diplomatic-political branch of the Defence Ministry, and Defence Minister Moshe Yaalon, spoke in public of one incident in which a Russian military aircraft had crossed over into Israeli airspace, without mishap. "It was immediately resolved," said Mr Yaalon.
On Tuesday, the prime minister made an even more significant disclosure. He said in a public appearance: "We operate in Syria from time to time to prevent it turning into another front against us. We act, of course, to prevent the transfer of deadly weaponry from Syria to Lebanon."
Over the past five weeks, there have been three reported attacks by Israeli aircraft in the Qalamoun region near the Syria-Lebanon border, and one other at an unknown location. While Israel has not taken direct responsibility for these or for any other similar attacks, they were almost certainly the operations Mr Netanyahu was referring to in his speech. The strikes are aimed at Hizbollah convoys, allegedly transferring weapons systems from Iran to its Lebanese and Syrian proxies.
In the words of one senior Israeli officer, Israel and Russia are "not standing on each other's balls in Syria". While the Russians provide air-cover for the Syrian Army, an Iranian expeditionary force and Hizbollah fighters, it turns a blind eye when Israel operates against its erstwhile allies. In the chaos of Syria, Israel is satisfied to see Russia usurping the Iranians as the main new power on its northern border.
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