CHICAGO -- In a recent speech that generated some excited chatter in the blogosphere, Jeh Johnson, the Pentagon’s chief lawyer, hinted that the armed conflict with al-Qaida may be coming to an end: “I do believe that on the present course, there will come a tipping point-a tipping point at which so many of the leaders and operatives of al-Qaida and its affiliates have been killed or captured, and the group is no longer able to attempt or launch a strategic attack against the United States, such that al-Qaida as we know it . . . has been effectively destroyed.”

The rose-colored-glasses perspective on this is as follows. The president obtained authority to wage war against al-Qaida from a statute called the Authorization for Use of Military Force, which Congress enacted shortly after 9/11. The AUMF triggered the president’s commander-in-chief power, which enables him to detain enemy combatants indefinitely and kill them with drones and other weapons. If the conflict with al-Qaida ends, then the president loses these authorities, must release or try detainees at Guantanamo Bay, and must stop using drones to kill people. Counterterrorism will go back to the domain of law enforcement, where it resided before 9/11. As Johnson himself notes, this means that terrorism will be handled by the police, and be governed by law enforcement norms-including Miranda warnings, search warrants, charges, trials, prison sentences, and all the other features of civilian due process. Civil liberties would awaken from its 11-year slumber.

But it is too early to celebrate. As Harvard law professor and Bush Justice Department official Jack Goldsmith has pointed out, Johnson’s speech contains many hedges and equivocations. Most important, although Johnson notes that the “core” of al-Qaida has suffered a significant lashing, its affiliates are alive and well, especially in the Middle East, where they appear to be flourishing. The AUMF identifies the affiliates of al-Qaida as the enemy, as well as al-Qaida itself. As long as those affiliates remain in existence, the United States will be at war with them. And because “al-Qaida” has become a kind of brand that any group can lay claim to, al-Qaida affiliates will be around as long as radical Islam is.

Moreover, even if al-Qaida and its affiliates are destroyed, it will make little difference for the president’s authority to use military force against future terrorist threats. The president will retain his authority under the Constitution, Article 2 of which has been interpreted to give the president the power to use military force against security threats even in the absence of congressional authorization. Johnson implicitly recognizes this point when he notes that if law enforcement can’t handle future terrorist threats, “our military assets (will be) available in reserve to address continuing and imminent terrorist threats.”

It is true that there is intense controversy among lawyers as to the scope of the president’s constitutional authority, with many on the left arguing that it is limited to repelling sudden attacks. But this is legal posturing. The president has strong incentives to protect Americans from terrorist attacks and the public largely approves of aggressive action, and therefore no one — not the public, nor Congress, nor the courts — will make a fuss if the president uses military force to counter a new terrorist threat to come.