An Even Bigger Threat

9/11 Ten Years After: Perspectives

In November 2001, Graham Allison wrote that “after Sept. 11, a nuclear terrorist attack can no longer be dismissed as an analyst’s fantasy.... As the international noose tightens around Al Qaeda’s neck, the group will become more desperate and audacious.” Ten years later, he says we have made some progress in keeping nuclear weapons out of terrorist groups’ hands.

On 9/11, 19 terrorists killed more Americans than the Japanese attack on Pearl Harbor. If the terrorists had been in possession of a nuclear weapon, the attack might have killed 300,000.

Post 9/11, President Bush, and now President Obama, have declared nuclear terrorism the biggest threat to American national security.

The United States has taken the lead in investing more than $10 billion and countless hours in securing and eliminating nuclear weapons and material worldwide.

Obama’s Nuclear Security Summit in 2010 focused exclusively on the threat. As a result of these efforts, thousands of weapons, and material that could have produced thousands more weapons are better secured than they were a decade ago. In Russia, which has the world’s largest stockpile of nuclear weapons and material, hundreds of sensitive sites have been secured. Seventeen countries have eliminated their weapons-usable material stockpiles entirely.

But to prevent a nuclear 9/11, all nuclear weapons and weapons-usable material everywhere must be secured to a “gold standard”— beyond the reach of terrorists or thieves.

On that agenda, much remains to be done. The ever-more-fragile state of Pakistan has the world’s most rapidly expanding nuclear arsenal. North Korea today has enough material for about 10 nuclear bombs. And Iran now has enough low-enriched uranium, if further processed, for four nuclear weapons. One of these weapons in the hands of terrorists could mean an “American Hiroshima.”

The price of success in preventing a nuclear 9/11 remains eternal vigor and vigilance.

Graham Allison is director of the Belfer Center for Science and International Affairs at Harvard’s Kennedy School of Government and a former assistant secretary of Defense.