resident Obama’s recent claim to have “contained” ISIS in Syria and Iraq exemplifies what’s wrong with his foreign policy. Whether or not we have contained ISIS—last November’s attack in Paris strongly argues we haven’t—the very pursuit of containment instead of victory is misguided. Containment is not winning, and in war, winning is everything.

But winning wars is difficult, often requiring unpopular sacrifices of lives and treasure. Containing problems, on the other hand, suggests that we needn’t make war, even if bombs are being dropped. At worst, we can engage in “limited war,” and pursue easily achieved goals requiring modest costs.

The limited-war doctrine dates from the early years of the Cold War. In the aftermath of WWII America and the Soviet Union established zones of influence on the Korean peninsula, divided by the 38th parallel—the border between the newly-minted countries of North and South Korea. When North Korean troops crossed the 38th parallel in 1950, the U.S. and its United Nations allies fought to defend South Korea. After several military setbacks, UN forces launched a successful offensive behind enemy lines at Inchon.

This success, however, led China to enter the war on North Korea’s side. (The two countries share a border at the Yalu River.) President Truman—commander of the U.S. troops, and effective commander of the joint UN command—ordered UN forces to stop. Allied military commander General Douglas MacArthur lobbied against Truman’s order, arguing that we should chase the Chinese back across the Yalu because “there is no substitute for victory.” In one of America’s signal affirmations of civilian supremacy over the military, Truman sacked MacArthur. The result was a retreat, not just from the Yalu, but all the way back to the 38th parallel. Having fought to a draw, the parties negotiated a “peace” and (supposedly) ended the war.

What are the fruits of this limited war? North and South Korea remain divided along the 38th parallel, now the Demilitarized Zone, or DMZ. North Korea, one of the most repressive, demonic regimes in the world, regularly threatens to use its nuclear arsenal against South Korea and other neighbors. Sixty years after “peace” was declared, some 30,000 American troops help protect South Korea .

History repeated itself two decades later in Vietnam. Again, operating under the influence of the doctrine of limited war, we sent troops into battle with one hand tied behind their backs. Having entered the war to “contain” the spread of communism in Southeast Asia, we declined (except occasionally, in secret) to cross international borders, even though the nation on the other side of the border (China, again) was providing men, materiel, and safe haven to our enemy.

Worse was the way in which we fought the war within Vietnam itself. America told its soldiers that their assignment was for a defined period: if they could stay alive for 13 months, they could go home, regardless of whether we were winning or losing. Suffice it to say, this was not a recipe for winning.

Our troops were further hampered by the metric of the “body count.” Instead of fighting to capture enemy-occupied territory, our military concentrated on simply killing as many Viet Cong as possible. The epitome of this misbegotten strategy was what came to be known as the Battle of Hamburger Hill. Over a period of ten days in 1969, U.S. forces assaulted a Viet Cong hillside redoubt, resulting in approximately 450 U.S. and 650 Viet Cong casualties. However, only days after winning the battle and taking control of the enemy’s position, U.S. forces withdrew. Having defined “victory” in terms of body count, we placed no importance on holding territory. As a result, the Viet Cong simply re-occupied their old positions and Hamburger Hill was, again, in enemy hands.

All these blunders were completely consistent with the doctrine of limited war: we weren’t in Vietnam to win, but to contain the enemy and negotiate a settlement.

Our failures in Korea and Vietnam should have taught us that “limited war” is a contradiction. War, once chosen, should only be limited by the defeat of our enemy. We should only go to war if we are prepared to win, which requires taking and holding the enemy’s home base—their territory. Unfortunately, the party that understands these lessons best is our current enemy, ISIS.

As an adherent of limited war, Obama advocates restraint and caution in our fight against ISIS. But the goal of ISIS is not détente with the West; it is our total destruction. ISIS doesn’t fight to contain us, but to control territory and consolidate its “caliphate.”

And ISIS clearly plans to expand its territory. The recent ISIS-sponsored massacres in Paris, the ISIS bombing of a Russian passenger plane in Egypt, and the ISIS-inspired hostage-taking in Mali should not be misinterpreted as merely a warning to “leave us alone.” The real message is “We are coming for you.”

President Obama seems to believe that defeating ISIS is a matter of killing the right bad guys through tactical aerial strikes. Since radical Islamists apparently want to die for their cause, one could argue that Obama’s strategy is a win-win solution for both sides.  However, as much as we would like to grant our enemies their wish, we can’t kill them all.

The way to defeat ISIS is to engage them on their home turf in Syria and Iraq. Accordingly, to destroy the caliphate, we must go to Syria and Iraq to capture and occupy every inch of ISIS territory. Without taking over their territory, they will continue to attract new recruits, and continue to attack the West. A war limited to airstrikes and the pursuit of a negotiated settlement will never defeat our enemy.

The only candidate seeking to succeed President Obama who understands this has been Senator Lindsey Graham. Backed by his mentor, Senator John McCain, Graham consistently called for a do-what-it-takes ground offensive against ISIS in Syria and Iraq. But now Senator Graham has dropped out of the race. After the Paris wake-up call, it did look like he might be joined in his commitment by Jeb Bush and maybe Chris Christie.  But, of course, Bush and Christie are also history. As for the rest of the Republican challengers, past and present, they either oppose US troop involvement in the Middle East or they prefer to avoid the issue and quibble over intelligence issues such as monitoring of phone records and better vetting of Syrian refugees. (Mr. Trump is perhaps a special case because it is anyone’s guess what he really believes.) On the Democrat side, the only candidate who even remotely supports a more active role for us in the fight against ISIS, Hillary Clinton, is still enamored with all things aerial like no-fly zones (by the way, ISIS has no air force) and, thus, she remains firmly stuck in the mud of the limited war doctrine.

Victory cannot be won solely by using air power. Syria and Iraq are not simply expanses of uninhabited desert where an enemy can be blasted to smithereens from thirty thousand feet, but densely populated countries with large urban areas, packed with civilians—and with embedded ISIS fighters. ISIS must be defeated the old-fashioned way: with boots on the ground. It is disheartening that neither Obama, nor any remaining 2016 presidential candidate for either party appears to understand this reality.