During the presidency of George W. Bush, and especially after the 11 September terrorist attacks of 2001, rumors circulated in major news sources that the U.S. was considering designing new nuclear weapons ("bunker-busting nukes") and resuming nuclear testing for reasons of stockpile stewardship. Republicans argued that small nuclear weapons appear more likely to be used than large nuclear weapons, and thus small nuclear weapons pose a more credible threat that has more of a deterrent effect against hostile behavior. Democrats counterargued that allowing the weapons could trigger an arms race. In 2003, the Senate Armed Services Committee voted to repeal the 1993 Spratt-Furse ban on the development of small nuclear weapons. This change was part of the 2004 fiscal year defense authorization. The Bush administration wanted the repeal so that they could develop weapons to address the threat from North Korea. "Low-yield weapons" (those with one-third the force of the bomb that was dropped on Hiroshima in 1945) were permitted to be developed.