Etymologically, the word comes from the French for rebirth, which is spelled 'renaissance'. Normally, it's prudent to take a live-and-let-live approach to the development of language as that's how language evolves, but in this instance the Americanised spelling is downright barbarous and not holding with the origins or spirit of the word. In this case, I'd argue that the American spelling isn't different in the way color or aluminum are, it's just wrong.
At least with aluminium the US spelling is the original spelling, it was just anglicised with an -ium ending to fit in with the other elements.
Yeah, it matches up with how Americans pronounce it, too. British English speakers (like me) pronounce it 'ren AY sonce', while Americans pronounce it 'ren uh sonce'.