In coming years, President Obama will decide whether to deploy a new class of weapons capable of reaching any corner of the earth from the United States in under an hour and with such accuracy and force that they would greatly diminish America’s reliance on its nuclear arsenal.
Yet even now, concerns about the technology are so strong that the Obama administration has acceded to a demand by Russia that the United States decommission one nuclear missile for every one of these conventional weapons fielded by the Pentagon. That provision, the White House said, is buried deep inside the New Start treaty that Mr. Obama and President Dmitri A. Medvedev signed in Prague two weeks ago.
Called Prompt Global Strike, the new weapon is designed to carry out tasks like picking off Osama bin Laden in a cave, if the right one could be found; taking out a North Korean missile while it is being rolled to the launch pad; or destroying an Iranian nuclear site — all without crossing the nuclear threshold. In theory, the weapon will hurl a conventional warhead of enormous weight at high speed and with pinpoint accuracy, generating the localized destructive power of a nuclear warhead.
The US military carried out a lethal strike on a vessel in the eastern Pacific, killing...
