The only thing preventing a nuclear attack at this point is the realization that Americans will retaliate with substantial force. Think in terms of our response after 9/11. Trillions spent for military operations in Afghanistan and Iraq, a new executive department dedicated to hunting down 'potential' terrorists and protecting airports and other public venues, and finally the willingness of people to accept invasions of privacy and reductions in personal liberty (Patriot Act) in a nation that whines when they must wait in line at the DMV.
Even the most avowed America hater must admit to some hesitation to use a nuclear weapon when they realize its going to provide ardent war hawks with concrete justification for even greater military adventures, tighter security, and stripping of liberty to promote public safety. Bush has been blasted because a 'smoking gun' of WMD was not found in Iraq. So, does anyone think a dirty nuke lit off in New York's Grand Central or Chicago's Union Station will help or hurt chances for thoughtful action?
With this said one may think, "Okay smart guy, you said yes to this question so why explanations as to why it will not happen?" Time and the attention span of people who don't like to wait in line at Starbucks, flip through 500 channels seeking something that will capture attention for about 15 minutes at a stretch, and a media establishment that decides every 11 days that a new crisis looms on our horizon (promptly forgetting the host of other unsolved disasters).
In addition to American and world ADD when it comes to issues and dangers there is the problem of just how prolific both the Allies and Communist were in producing the tools to make large, medium, and small scale nuclear weapons. Just take the Savannah River facility and think about the thousands of plugs of plutonium produced from the 50s to the 90s. We used a few in above and under ground testing but that still leaves lots of very radioactive basic components lying around. Storage and disposal is a continued concern in that we must take precautions to transport and safely store these building blocks for a nuclear weapons. Do you think those charged with security and monitoring are above economics or politics? The 'enemy' spent a tidy sum moving people, weapons, and planning for not one but two attacks on the World Trade Center. Money spent could have already bought components for building a suit case size dirty bomb.
Now think about the fall of the Soviet Union. Talk about people willing for ideological and economic reasons to provide a third party with bomb making material to get back at the victorious decadent West, you have it in military and political leaders who lost the Cold War. Remember the same U.N. that is overrun with corruption and weak leadership is expected along with NATO to monitor the transport and storage of former Soviet nukes. Scary to think especially when you consider just how paranoid Soviet leadership was when it came to nuclear stockpiles. So, do the records reveal all the places where weapons could be?
A good film The God of War with Nick Cage dealt with conventional weapons that helped a variety of friends and foes of the United States wage endless war on neighbors. Is it a stretch to think nuclear weapons are sacrosanct? Heck, our best friends in the Middle East, the Israeli's have used spies and clandestine deals to become a nuclear power. I think it is logical that friends like Saddam, Khaddfi, and a host of other Third World thugs enjoyed both nuclear and conventional 'gifts' from a Soviet system at odds with Western democracies.
Yes it is sad but I think its not a matter of if but when. 9/11 is fresh in the minds of Americans but our foes have spent decades learning to hate us. These foes are undeterred by setbacks (think of the first attack on the Twin Towers) and have a vision of heaven that pays off if they die killing people of the Great Satan.
One last thought, much of the terrorism we decry had occurred for years in Europe, Asia, and Africa. It did not become newsworthy until it killed Americans on American soil. Think about the acts of terror abroad that caused no response until Americans were killed. Our air raid on Libya was retaliation for the bombing of a German nightclub frequented by American service people. The analysts and intelligence 'experts' thought such things could not happen in America. When it did we retaliated and for a time bought ourselves a reprieve. That is by no means an end to the possibility of another attack, no, only a break in the continued warfare that has plagued this planet since the first man picked up a weapon to rule over or take from another.