Or, in modern era, was the US really at peace with Russia?
They were at war with Russia: it was called The Cold War.
According to Mitsugi Saotome:
'The kanji is made up of the character hoko
which means "spear" and symbolizes weapons in general, and the character todomeru
, which means "to stop". Thus bu
means to stop weapons. [...] As the kanji implies, the original intent of bu
was to stop war, to protect people from weapons.'
(Taken from The Principles of Aikido
by Mitsugi Saotome; pp. 191-2)