President Barack Obama’s administration has upped the requirements needed to explode a city-leveling bomb and for the first time places countries without nuclear weapons off-limits from nuclear attack.

“The United States would only consider the use of nuclear weapons in extreme circumstances to defend the vital interests of the United States or its allies and partners,” according to a Defense Department statement this morning.

At the same time, the guideline, which outlines everything from the size of nuclear warhead stockpiles to negotiating stances with Russia, said the U.S. would “modernize” its arsenal, laying out the administration’s justification for why the U.S. needs its own newer and “safer” arsenal of bombs and delivery vehicles that the Pentagon says acts as a deterrent to a nuclear attack, especially from Iran and North Korea.

Download:

http://www.defense.gov/npr/docs/2010%20Nuclear%20Posture%20Review%20Report.pdf