It says - "Refrain from the threat or use of force against the territorial integrity or political independence of the signatories to the memorandum, and undertake that none of their weapons will ever be used against these countries, except in cases of self-defense or otherwise in accordance with the Charter of the United Nations." and "Seek immediate Security Council action to provide assistance to the signatory if they "should become a victim of an act of aggression or an object of a threat of aggression in which nuclear weapons are used".".

Budapest memorandum is not a treaty or military alliance or a security guarantee like NATO 



Bell_curve

That's ok, but doesn't mean you should not support weak good guys against bullying from the bad guys. USA has done a lot of bad things, but Russia is worse. Besides, according to Budapest memorandum, it's duty for USA to support Ukraine, as they were one of countries guarateering territorial integrity of Ukraine.