The battle for Mosul in Iraq is barely two weeks old. As of this writing, coalition forces have yet to even enter the city proper. Yet already, U.S. officials have announced the beginning of the attack on the Syrian base of ISIS support in Raqqa. It is distressing to realize senior American foreign-policy and defense officials remain unaware of the list of critical factors that, under the current circumstances, should argue persuasively against the contemplation of such an operation.

Though Iraqi Security Forces have to date successfully ejected ISIS fighters from a number of sizeable urban centers in Iraq, they have not fought in a city of Mosul’s size, nor against a desperate enemy with its back to the wall. It is far from certain the ISF and other coalition troops will withstand what might end up being a meat grinder of a battle.

Moreover, the coalition of forces currently arrayed against ISIS in Mosul are composed of militias, some of whom are strongly antithetical to each other. It is still not certain whether Turkish troops, stationed just outside of Mosul, will play a neutral, supporting, or destabilizing role in the battle. For the coalition to succeed, many factors must achieve “best-case scenario” outcomes. Yet for all these potential liabilities and uncertainty in the battle to liberate Mosul, they are nothing compared to the mountainous tactical and strategic challenges inherent in trying to oust ISIS from Raqqa.

In the surrounding environs of Mosul there is a fully supported state army, several well-armed and -equipped militias, and the unambiguous support of U.S. ground and intelligence troops. Outside of Raqqa, none of those things exist. There is no state-supported military unit leading the assault, no allied militia that have the luxury of staging outside Raqqa to prepare for the attack in security, and no resupply lines through friendly territory. The disadvantages only get worse at the political level.

Critical to U.S. plans for success is having both Kurdish fighters and the Turkish Armed Forces cooperating to achieve the common goal of expelling ISIS from Raqqa. American Lt. Gen. Stephen Townsend admits that the “tough” question of how the two mortal enemies are expected to work together hasn’t been resolved. As a reminder, barely a week ago Turkey deliberately launched a devastating aerial attack that killed and wounded hundreds of American-supported Kurdish fighters in northern Syria. On Wednesday, Salih Muslim, a Kurdish leader of the Democratic Union Party (PYD) in Syria, said it is important to take Raqqa, “but one point which is bothering us is that, if we go toward Raqqa, we will be stabbed from the back [by Turkey].” His fears are justified.

In August, a Kurdish-led coalition liberated the town of Manbij, just south of the Turkish/Syrian border. Taking Manbij cut a major supply route for ISIS between Turkey and Raqqa, as well as making Turkey safer by denying ISIS an entry point into Turkey. One resident of Manbij said of the liberating Kurdish troops, “You are our children, you are our heroes, you are the blood of our hearts.” The Kurds’ reward for this feat?

Turkish president Recep Tayyip Erdoğan named the PYD as an enemy to be militarily defeated. “Manbij will be cleansed of PYD elements,” Erdoğan said. “We have no tolerance on this issue and we expressed our position to our partners in the coalition.” What possible assurances could the United States give to the Kurds that upon successful liberation of Raqqa, the Turkish army isn’t going to turn on them? Why would the Turks bomb the Kurdish troops one day and then work with them the next, or allow the Kurds to maintain a presence after liberating Raqqa? There is no recognizable logic in these unsubstantiated hopes.

Yet even if somehow the gulf of differences between Turkey and the Kurdish fighters could be overcome, and ISIS were kicked out of Raqqa, it would not diminish the terrorist threat to the United States. Last week, Director of National Intelligence James Clapper was interviewed by Charlie Rose and was asked what threat ISIS will pose after it loses both Mosul and Raqqa. Clapper said ISIS is, “probably not going to go away, and it’ll morph into something else or other similar extremist groups will be spawned. And I believe we’re going to be in the business of suppressing these extremist movements for a long time to come.” That admission is startlingly honest and equally significant.

Even the director of national intelligence admits depriving ISIS of territory isn’t going to make America safer. This would only be the first negative consequence of a “successful” (on the tactical level) Raqqa liberation.

If the group of allied “moderate” rebels defeated ISIS and occupied Raqqa, they would be an island within a sea of civil war. They would still be the enemies of the Syrian regime and would again be targeted by Damascus and its allies. Would the United States then set up a no-fly zone and use lethal power to defend the rebels in the city from Syria and its allies? Doing so might put the United States in military opposition to Russian and Iranian military personnel, and require the UN.

Would the United States be willing risk a major war by attacking and destroying Syrian ground troops, Russian attack jets and Iranian ground forces in defense of a group of Islamic rebels whose governing inclinations are unknown? If American military personnel destroy or kill Syrian, Iranian, or Russian troops, it is certain these nations would respond in some way antithetical to U.S. interests.

Have U.S. officials considered these near-certain responses to our attempt to aid Syria’s civil war opponents? The objective of American foreign policy has to result in outcomes beneficial to U.S. interests. Attempting to wrest control of a major city, in a hostile foreign land enmeshed in a years-long civil war, has—literally—no chance of producing positive outcomes for our country. It could, however, result in deadly consequences.

Without doubt the most dangerous outcome for the United States would be if, in defense of rebels in Raqqa, a U.S. missile shoots down a Russian plane, kills Russian ground troops—or if a Russian antiaircraft missile shoots down and kills American pilots.

How each government would respond to its military personnel being killed by the other is unknown, but the reaction could spiral out of control. The result could degenerate to the point of a nuclear exchange; that such a possibility can’t be ruled out is terrifying.

Why would any responsible leader in the United States even consider taking action that has almost no chance of accomplishing a positive outcome for U.S. interests, yet does have enormous negative possibilities? I can categorically state there is nothing in Syria that is worth the strategic risk of spawning a major war with the world’s largest nuclear superpower.

It is long past time American policymakers accept the fact that military power cannot solve every international problem, however hard some might wish it were so. Moreover, U.S. leaders must stop pressing for objectives of dubious tactical value at the risk of strategic loss. Washington ignores these warnings to its peril. Unfortunately, the 330 million citizens of this country will be the ones who ultimately pay the price if things go bad.

Daniel L. Davis is a retired U.S. Army colonel who served multiple tours in Afghanistan. He is a senior fellow with Defense Priorities. Follow him on Twitter @DanielLDavis1.

Image: U.S. soldiers fire an M777 howitzer at Kara Soar Base, Iraq. DVIDSHUB/Public domain