It is clear that terrorists want to obtain a nuclear bomb, as both Osama bin Laden's public statements and the documents outlining al-Qaeda's nuclear program make clear. If terrorists could obtain the highly enriched uranium or plutonium that is an essential component of a nuclear bomb, making a bomb might well be within the capabilities of a large and sophisticated terrorist group. The risk of this happening is real, since hundreds of tons of nuclear material in dozens of countries remain dangerously vulnerable to theft. If terrorists could steal, buy, or make a nuclear bomb, there is a high probability that it could be smuggled into the United States. Even a crude terrorist bomb could be capable of incinerating the heart of any U.S. city. If the existing stockpiles of nuclear weapons and materials can be effectively secured and prevented from falling into terrorist hands, a nuclear terrorist attack can be prevented. The most critical and cost-effective way to prevent nuclear terrorism is to secure nuclear weapons and their essential ingredients at their sources. The United States and other states in the international community have a wide range of efforts underway to improve security for nuclear weapons and materials at vulnerable sites in the former Soviet Union and around the world. This has involved the destruction of thousands of nuclear weapons, improving security for scores of vulnerable nuclear sites, and providing at least temporary re-employment for thousands of nuclear weapons scientists and workers who might otherwise market their expertise and/or materials to the highest bidder. This paper details these security efforts. There have been a number of setbacks in the past year, however. This paper lists some of these setbacks and obstacles to progress. Three essential elements of an accelerated and strengthened effort are proposed in this paper as follows: removing the nuclear material entirely from the world's most vulnerable sites; accelerating and strengthening the effort in Russia, where the largest stockpile of potentially vulnerable nuclear materials still exist; and building a fast-paced global coalition to improve security for nuclear materials around the world. 49 notes