Just before deciding on Wednesday to remove U.S. forces from Syria, President Trump had a long telephone conversation with his Turkish counterpart, Recep Tayyip Erdogan. It appears some sort of agreement between the two—including a commitment by Ankara to purchase anti-missile missiles from Washington rather than Moscow—influenced the decision. The American president reported another conversation with Erdogan yesterday. Steven A. Cook examines the role Turkey will play in the future of Syria.

Donald Trump’s announcement betrays Washington’s primary partner on the ground, the Kurdish-led Syrian Democratic Forces (SDF), which control nearly one-third of Syria. It leaves other regional allies, especially Israel, more vulnerable to Iran and Hizballah, which have a presence in Syria. Without the United States in Syria, regional actors will depend on Russia to achieve their interests.

Trump’s decision also boosts Turkey. The Turkish government has sought an end to the United States’ military and diplomatic relationship with the SDF. Ankara argues, [credibly], that the SDF’s primary component, the Peoples’ Protection Units (YPG), are part of the Kurdistan Workers’ Party (PKK), which has waged a terrorist campaign against Turkey for almost 35 years. Yet the advantages to Turkey may be short-lived. . . . [I]f the Turkish military does invade [northeastern Syria] to try to destroy the YPG and render Syrian Kurdish autonomy moot, Turkey could find itself locked in an irregular war in a foreign country. . . .

In addition, the YPG is likely to turn directly to the Syrian and Russian governments in the wake of the Trump administration’s decision. . . . That would raise the possibility of a confrontation between Syria and Turkey. . . . Russia, which provides diplomatic and military support to Syrian Kurdish forces, can be expected to play all sides of the issue, ensuring it has maximum leverage with Ankara and further weakening Turkey’s already frayed ties with NATO and Europe. . . .

Vladimir Putin . . . is now the undisputed broker of the future of Syria, but Moscow will have to handle the competing interests of Syria and Turkey. If Putin can manage this complicated situation without a major confrontation between the Turks and Kurds, and between the Turks and Syrians, he will solidify his role as a regional leader.

Two extraordinary events demonstrate something important about Israel’s most fervent adversaries. One was a speech given at something called The People’s Forum (funded generously by Goldman Sachs), which stated, “When the state of Israel is finally destroyed and erased from history, that will be the single most important blow we can give to destroying capitalism and imperialism.”

The suggestion that this tiny state is the linchpin of a global, centuries-old phenomenon like capitalism goes well beyond anything resembling rational criticism. Even if Israel were guilty of genocide, apartheid, and oppression—which of course it is not—it would not follow that its destruction would help end capitalism or imperialism.

The other was an anti-Israel protest that took place in front of New York City’s Memorial Sloan Kettering Cancer Center, deemed “complicit” in Israel’s evils. At organizers’ urging, participants shouted their slogans at kids in the cancer ward, who were watching from the windows. Given Hamas’s indifference toward the lives of Gazan children, such callousness toward non-Palestinian children from Hamas’s Western allies shouldn’t be surprising. The protest—like the abovementioned speech—deliberately conveyed the message that Israel is the ultimate evil and its destruction the ultimate good, cancer patients be damned.

The fact that Israel’s adversaries are almost comically perverse does not mean that they can be dismissed. If its allies fail to understand the obsessive and irrational hatred that it faces, they cannot effectively help it defend itself.