What does Syrian despot Bashar al-Assad know that President Obama and Secretary of State John Kerry don’t — or that they won’t admit?

Simply this: Their nuclear deal will leave Iran in a much stronger position.

In an interview Tuesday with the Hezbollah terrorists’ Al-Manar TV network, Assad — who last month hailed the deal as “a great victory for Iran” — said it would strengthen Tehran internationally, and so help him.

“The power of Iran is the power of Syria,” Assad said of the regime that bolsters him with troops, weaponry and cash, “and a victory for Syria is a victory for Iran.”

Makes sense. The deal hands Tehran around $150 billion in the first year, along with longer-term sanctions relief. If Iran uses just 10 percent of that cash to support its terrorist allies, that “would have a potentially big impact in places like Syria, Iraq and Yemen,” notes David Rothkopf, the CEO of Foreign Policy magazine.

Tehran sees it that way, too. Ali-Akbar Veleyati, a top adviser to supreme leader Ali Khamenei, confirmed over the weekend that the deal gives Iran “more power to support its friends in the region.”

In Syria, support for Tehran’s friends means more aid to a regime whose atrocity-ridden war to stay in power has already inflicted 230,000 civilian casualties.

Meanwhile, Ali Larijani, the speaker of Iran’s parliament, just reaffirmed that Tehran’s goal remains the destruction of Israel.

British Foreign Secretary Philip Hammond had announced that Iran is adopting “a more nuanced approach” toward the Jewish state. Not so, said a Larijani spokeswoman: “Our positions against the usurper Zionist regime have not changed at all. . . Israel should be annihilated and this is our ultimate slogan.”

Supporters of this deal should be under no illusions: In the hope of delaying Iran’s entry into the nuclear club, it hands a vast windfall to a regime that sponsors terror and subversion across the region, and remains intent on annihilating Israel.