President George W. Bush, and his aides, could hardly wait to get rid of all those tiresome arms-control treaties when they took office. They tore up the 1972 antiballistic missile treaty to make way for a still largely pie-in-the-sky missile defence system. They opposed the Comprehensive Nuclear Test Ban Treaty and never made a serious effort to win a ban on the production of fissile material.

While Bush and his team were ridiculing treaties and arms control negotiations as “old think,” North Korea tested a nuclear device, Iran has been working overtime to produce nuclear fuel and many other countries are weighing whether they need to get into the nuclear game. President Obama pledged to address these dangers when he was campaigning. In her recent confirmation hearing, Secretary of State Hillary Rodham Clinton argued that America’s best hope of doing that is to restore treaties and a rules-based system.

Bush repeatedly warned about the dangers of nuclear weapons falling into the hands of terrorists. He was right. But he never put in place the strategy needed to ensure that that never happens. And he weakened some of this country’s most fundamental defences, including its credibility. As president, Obama must do better. He can start by restoring the rules of the game.