Russian President Putin Lowers Threshold For Using Nuclear Weapons

RUSSIAN President Vladimir Putin on Tuesday signed a revised nuclear doctrine declaring that a conventional attack on Russia by any nation that is supported by a nuclear power will be considered a joint attack on his country.

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The signing of the doctrine, which says that any massive aerial attack on Russia could trigger a nuclear response, reflects Putin's readiness to threaten use of the country's nuclear arsenal to force the West to back down as Moscow presses a slow-moving offensive in Ukraine.