assure, ensure, insure

Jeebus, who invented this stupid language? Why have similar sounding words flowered when perfectly good assemblies of letters, such as 'glinfarb,' lie fallow?

assure: to state with confidence
ensure: to guarantee; to make certain
insure: to guarantee against loss (as in to issue an insurance policy)

Luke assured Wedge that exploiting the weakness in the Death Star was no more difficult than shooting womprats in his T-16 back home. (Wow, Luke, I wanna party with you, dude.)

Admiral Ozzel ensured his death by bringing the Imperial fleet out of hyperspace too close to the Hoth system (whatever the hell that's supposed to mean). Putting a whoopie cushion under Vader's chair earlier that morning wasn't too bright either.

The Rebellion took steps to ensure the location of their base was hidden from the Empire.

The Jedi policy insures her life against laser blasts but not against the consequences of using the Jedi Mind Trick in Vegas.