President Donald Trump’s sudden decision via tweet to pull all U.S. troops out of Syria opened the door for a massacre of our Kurdish allies by the Turks.

Stung by angry GOP critics, he and administration officials have been scrambling to show they won’t leave Syrian Kurds in the lurch. In a series of tweets and phone calls with Turkish President Recep Tayyip Erdoğan, Trump has called for a “safe zone” to protect the bulk of Syrian Kurds who live near the Turkish border. The president seems blind to the fact that Erdoğan interprets the “safe zone” to mean Turks can cleanse our Kurdish allies from it.

Indeed, Trump’s Syria tweets have only increased the chances of bloodshed on the border. The president’s hasty pullout decision (opposed by his entire security team) has the administration scurrying for a strategy to prevent Iran, Russia, and ISIS from profiting from the U.S. exit.

Meantime, the unplanned U.S. pullout has already emboldened a latent insurgency by remaining ISIS fighters; four Americans deployed to Syria were killed by a suicide bomber last week.

The tale of Trump’s proposed “safe zone” illustrates the chaos caused when an ill-informed president makes policy by tweet.

Last Sunday Trump tweeted his call to “create a 20 mile safe zone” for Kurds, with no further explanation. Trump emissaries traveling the region were blindsided by the proposal. And it has become clear that the Turkish definition of safe zone is entirely different from Trump’s.

The Kurdish region of Syria, which has functioned as a virtually autonomous area since the start of Syria’s civil war, runs along the border with Turkey. The main Kurdish political party, the Democratic Political Union, or PYD, fields a militia, known as the YPG which was the main ground force that defeated the ISIS caliphate in Syria. It works closely with the 2,000 U.S. forces in the country.

However, the Turks call the YPG fighters “terrorists” and view them as allies of Kurdish rebels inside Turkey. The United States disagrees, distinguishing Syrian Kurdish fighters from their Turkish cousins. And, indeed, Syrian Kurdish fighters have never attacked Turkey across the Syrian border.

Bottom line: Erdoğan views “the safe zone” as an invitation for Turks to invade Syria and smash America’s Syrian allies. Erdoğan told Trump last week that “a 20-mile security zone along the Syrian border will be set up by us.”

To get the Syrian Kurdish view on the “safe zone,” I phoned to the Kurdish capital of Qamishli and spoke with Salih Muslim, former co-president of the PYD party. Muslim quickly replied: “Turkey talks about a zone that means there would be a Turkish occupation. If Turkey came across the border, its main aim would be to kill Kurds, throw all of them out, and replace them with Arab refugees living in Turkey, including jihadi families.”

Muslim pointed out that the main Syrian Kurdish cities of Qamishli and Kobanî would fall within that 20-mile zone.

As a warning, Muslim pointed to the experience of Afrin, a once predominantly Kurdish town and district west of the main Kurdish region. No U.S. troops were stationed there. So Turkish soldiers crossed the border and drove out much of the Kurdish population, replacing them with Syrian Arab refugees.

Muslim says Syrian Kurds would welcome a safe zone if it were monitored “by the United Nations, by the United States, or anyone.” But not occupied by Turks.

U.S. officials have been visiting Turkey trying to get Erdoğan’s agreement to protect the Syrian Kurds. But he refused to meet Trump’s national security adviser, John Bolton, after Bolton publicly insisted that our Kurdish allies must be protected. He continues to label the YPG as terrorists.

Trump tweeted that “Will devastate Turkey economically if they hit Kurds,” which Secretary of State Mike Pompeo interpreted to mean sanctions. But neither Trump nor Pompeo has clarified that our Kurdish fighting allies will be protected. Nor would sanctions help if Turkey had already invaded the Kurdish region.

And given Trump’s habit of changing his mind, this vague warning is unlikely to impact Erdoğan’s determination to crush the Kurds.

Sadly, Trump’s policy-making via tweet squandered any chance of getting a quid pro quo for a U.S. withdrawal. “This administration failed markedly to condition withdrawal on something,” says Aaron Stein, who heads the Middle East program at Philadelphia’s Foreign Policy Research Institute. “Now we are negotiating if or how Turkey should enter Syria. This should have happened before the withdrawal.”

Rather than use a planned withdrawal strategically to pressure Russia or the Syrian regime, or Turkey, Trump gave away America’s leverage for nothing.

“Tell the American people,” said Muslim, “that for four years we worked together. This mutual trust, you can’t find it elsewhere in the region. We don’t want to lose that trust between both sides just because of Turkish tricks.”