The Red Horseman by Stephen Coonts

As the infrastructure of the Soviet Union crumbles before the world's eyes, twenty thousand nuclear weapons, once under the command of the Soviet military, are up for grabs - and U.S. intelligence believes they may soon appear on the open market.

Rear Admiral Jake Grafton, Deputy Director of the Defense Intelligence Agency, is dispatched to Moscos. His assignment: ensure that the weapons are destroyed before they disappear into the Middle Eastern terrorist pipe. But Grafton discovers that unidentifed Americans officials wants his mission to fail - and will go to any length to stop it. Meanwhile, off the coast of the Canary Islands, the body of British billionaire and media magnate Nigel Keren has been found floating in the sea near his yatch. Grafton's contacts in Israeli intelligence have evidence that he was the victim of a hit squad from within the CIA. It's the kind of knowledge that could prove fatal, but Grafton can't back off: if the freelance operation succeeds, Middle East hostility could explode into an international conflagration. The only thing Grafton knows for sure is that he has been targeted for assasination, and the conspiracy is clearly stamped: Made in America.