Former Secretary of State John Kerry complained Thursday that President Donald Trump was ruining everything he and former President Barack Obama achieved with the Iran deal.

“He put his disdain for anything done by the last administration ahead of his duty to keep the country safe,” Kerry wrote in a mournful 1,000 word op-ed for the New York Times. The former secretary of state is currently supporting former Vice President Joe Biden for president and campaigning for him in Iowa.

Kerry argued the Iran nuclear deal was working, but Trump threw it all away, which only empowered Iran’s Quds Force Commander Qasem Suleimani.

“There were no missile attacks on United States facilities. No ships were being detained or sabotaged in the Persian Gulf,” he wrote about the state of the Middle East under the deal. “There were no protesters breaching our embassy in Baghdad. Iraq welcomed our presence fighting ISIS.”

Kerry even said that although Suleimani was a “sworn” enemy of the United States, America benefited from his efforts to fight ISIS.

“Occasionally, when American and Iranian interests aligned, as they did in fighting ISIS, we were the serendipitous beneficiaries of his relationships and levers, as were the Iraqis,” he said referring to Suleimani. “But this was a rare exception.”

Kerry even praised Iran’s response after they detained 12 American sailors in 2016, thanks to the “foundation of diplomacy” laid by the Obama administration.

“In 2016, we defused deep disagreements with Iran over prisoners and averted conflict when American sailors inadvertently entered Iranian waters and were detained by Iranian forces,” he wrote.

The failed 2004 Democrat presidential candidate accused Trump of alienating American allies in the Middle East and acting “recklessly” without a strategy.

“We have been left with an incoherent Iran and Iraq policy that has made the region more dangerous and put Americans at greater risk,” he wrote.

Kerry praised former Secretary of State Rex Tillerson and Secretary of Defense James Mattis for arguing in favor of the agreement and criticized current Secretary of State Mike Pompeo for supporting the president.

The former secretary of state warned of a repeat of the Iraq war or Vietnam under Trump, warning young Americans were frightened about dying in an upcoming war with Iran.

“Our diplomacy should not be defined by bluster, threats and brinkmanship, tweets or temper tantrums, but by a vision for peace and security addressing multiple interests of the region,” he wrote.