武 military

Hippies see the military and yell BOO!! BABY KILLERS!!

There is only one ritual that makes the military stop what they are doing even in the middle of a big battle : Hammer Time.

weapon ★★☆☆☆
武 (military) + 器 (instrument) = 武器 (weapon)

weapon: has the nuance of sword or small gun.

martial arts ★★☆☆☆
武 (military) + 道 (street) = 武道 (martial arts)

samurai ★★☆☆☆
武 (military) + 士 (samurai radical) = 武士 (samurai)

White kids say 'samurai', but real Japanese usually say ぶし. It can also be used to refer to the whole social class, as in　武士精神 （ぶしせいしん = samruai spirit) or　武士道 （ぶしどう = the honor-code of the samurai)