What President Barack Obama and British Prime Minister David Cameron didn't say during last week's joint news conference may have mattered more than what they did say. The omissions could lead to a grave setback in the war on terror and deadly results for the Afghan people.
The president and prime minister declared their solidarity on the Afghanistan war. Both leaders "reaffirmed our commitment to the overall strategy," in Mr. Cameron's words. Mr. Obama said that approach aimed to "build Afghan capacity so Afghans can take responsibility for their future," a point Mr. Cameron called "a key part" of the coalition's strategy.
All well and good. But neither leader uttered the word "victory" or "win" or any other similar phrase. They made it sound as if the strategic goal was to stand up the Afghan security forces, leave as soon as that was done, and hope the locals were up to keeping things together.
Neither man called for the defeat of the Taliban or declared its return to power unacceptable. Instead, Mr. Obama offered a lesser goal, namely to "break the Taliban's momentum." That is hardly a strategy that will galvanize people—as the King James Bible expressed it, "For if the trumpet give an uncertain sound, who shall prepare himself to the battle?"
Nor did Messrs. Obama or Cameron emphasize, as their predecessors did, the importance of liberty and human rights in Afghanistan. One of the remarkable achievements of the removal of the Taliban was the emergence of a nascent (if still imperfect) Afghan democracy, one that respects the rights of Afghan women. It would be a brutal betrayal to allow these rights to be extinguished.
Wars involve tactical shifts and adjustments. But they also involve "red lines"—and in Afghanistan, the red line must be to defeat al Qaeda and the irreconcilable elements of the Taliban, and to keep them from seizing power again.
The American and British people who are being asked to support this costly effort must know that is our objective. So must the Afghan people, who have seen much the last year to raise doubts about our resolve. And so must the Taliban and al Qaeda. America's enemies need to understand one thing above all else: They cannot outlast us and, if they try, they will be broken and defeated.
Victory in Afghanistan requires two things: the right strategy and the resolve to see it through. Mr. Obama wisely recruited Gen. David Petraeus to head the Afghan campaign. There is no one better equipped to execute a successful counterinsurgency campaign. He is both the father of the "surge" in Iraq and the person most responsible for implementing it. If Gen. Petraeus has the time and support he needs, he can bring similar success in Afghanistan.
But is Mr. Obama's heart in this fight? The commander in chief has said stunningly little about the war. He rarely explains to the American people what is happening or asks for their support.
Some congressional Democrats are growing restive, speaking more often and more loudly against the war and now voting against its funding. Ordinary Americans will also come to question the mission if the goal is not victory. Mr. Obama needs to deal with this by making it clear that when it comes to Afghanistan, he's all in.
Winston Churchill demonstrated that in war, words matter. They signal resolve or weakness, fortitude or doubt. Right now, the uncertain trumpet of Mr. Obama's words—those he has said and those he has chosen not to say—is emboldening adversaries, alarming allies, undermining confidence in the U.S., and dispiriting those who fight in dark and dangerous places for our security and liberty.
The president can and must correct those impressions—beginning with an unambiguous statement that America will stay and get the job done. Only the president can reassure our partners and allies, and strike the fear of God into our enemies. The world is looking for him to act as a commander in chief.
Mr. Obama has acted impressively so far on Afghanistan. He changed strategy based on facts on the ground, increased our troops by tens of thousands, and picked exactly the right man to lead our military into battle.
The president has the right pieces in place. Now he needs to signal to the world that he believes in the cause with all his heart. Let's hope he does.