Well known as the cry of Japanese soldiers fighting a hopeless war of choice caused by the depraved idiocy of their leaders which brought catastrophe on their nation. Clearly topical (except for the catastrophe I assume and hope). They shouted it when they were in an almost hopeless position which they changed into an immediate catastrophe by attacking (a tactic called "doubling down" or "the surge").
Literally it means
Ten Thousand Years.
John McCain's rallying cry is, you guessed it, Banzai ! That is "stay in Iraq for Banzai".
Political sepukku ? I sure hope so.
But it makes a funky video