Read also: Russia can start ground invasion of NATO countries without using nuclear weapons – Zelenskyy According to the source, Washington also sees no reason to adjust its nuclear stance after recent comments by Russian President Vladimir Putin on Moscow’s long-standing nuclear doctrine. The Kremlin leader previously stated that if U.S. troops were to be deployed to Ukraine, Russia would “treat them as aggressors.” Putin claiming that Russia “cannot be defeated on the battlefield,” a realization he suggests the West has come to understand. Meanwhile, the U.S. official said the dictator, “app…