Six months ago, President Barack Obama told the American people that the end of the U.S. war against al-Qaeda was approaching. Three months later, a threat from al-Qaeda’s Yemen branch shuttered 18 U.S. diplomatic missions across much of the Muslim world. Just last month, the administration called al-Qaeda’s Iraq and Syria chapter “a transnational threat network.”

So the question presents itself: Was the president wrong? The answer depends on the meaning of al-Qaeda -- and on the meaning of war.

In both cases, new definitions lead to new strategies. They may rely less on ground forces and targeted killings from drones, though neither can be abandoned, and more on diplomacy, intelligence and other international forces. And they will require more involvement from Congress.

Al-Qaeda’s core group, once headed by Osama bin Laden and now led by Ayman al-Zawahiri, is on the “path to defeat,” as the president said in May. In the Middle East and South Asia, however, where al-Qaeda was born, its affiliates pose real dangers to the U.S. These challenges can’t be met with diplomacy, law enforcement and intelligence activity alone. So war against this metastasized al-Qaeda must continue.

But the U.S. needn’t always take the lead. In Africa, the U.S. has let other parties confront two existing Islamist groups that have taken on the al-Qaeda mantle: the French in Mali and the African Union in Somalia.

Notably -- and appropriately -- the Obama administration has reduced its commitment of U.S. ground forces in the fights against terrorism. The U.S. withdrew its troops from Iraq in 2011 and has ruled out sending any back. U.S. troops in Afghanistan are scheduled to leave by the end of next year.

The Afghanistan withdrawal, however, raises concerns that al-Qaeda’s core group, which was reduced to ineffectiveness by U.S. drone strikes and appears to be unmolested by Pakistani authorities, may revive. That’s reason enough for the U.S. and Afghanistan to agree on terms that would allow the U.S. to leave behind a significant military contingent after 2014 and retain the ability to launch drones from Afghanistan.

The lack of such an agreement with Iraq hampers the U.S. ability to help President Nouri al-Maliki cope with al-Qaeda in Iraq and Syria, which has played a major role in sectarian violence in Iraq that has killed 7,000 people this year.

The group has not demonstrated the ability to strike beyond the region. But that could change -- especially if, together with the other al-Qaeda affiliate in Syria, it liberates a portion of Syria and turns it into a base for exporting jihad. Already, hundreds of foreign jihadis from Europe, Asia and North Africa have been drawn to Syria to fight for al-Qaeda and may pose threats when they return home.

The most dangerous al-Qaeda presence to the U.S. remains the one in Yemen: al-Qaeda in the Arabian Peninsula. It is the only part of the network apart from the core known to have directed attacks against the U.S. homeland: its foiled plots to bomb U.S.-bound airliners in 2009 and 2010.

With backing from the U.S. military, Yemeni forces regained control of AQAP’s southern strongholds in June 2012. Still, the group remains strong, and in August the U.S. launched eight drone strikes in Yemen -- four times as many as usual since Obama announced his restrictions on targeted killings.

Those restrictions are a start to rewriting the rules of the new war. But they don’t go far enough. Both the Bush and Obama administrations have used the Authorization for the Use of Military Force passed by Congress just after the Sept. 11 attacks as a basis for fighting al-Qaeda’s associated forces. With the battle no longer focused on the al-Qaeda core and its Taliban protectors, this original authorization has outlived its usefulness. The president and Congress are overdue for discussions to refine the authorization for war.

Obama was right to abandon the GWOT, George W. Bush’s acronym for a global war on terror, which identified a tactic rather than an enemy. But there are still terrorists who threaten the U.S. around the globe, and the U.S. still needs to wage war against them.

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