Her lifetime achievements in the academic world, in the legal world and the judicial world are unchallengeable.

CNN: Commentary: Don't go to war over Sotomayor

The decision leaves the election results certified by the Florida House of Representatives--but not by the state senate--earlier yesterday unchallenged and unchallengeable.

FORBES: Top Of The News: Supremes Vote For Bush

They launch overweening projects fuelled by the perception of unchallengeable power.

BBC: How the fate of Europe could be decided 'within hours'

The creation of Class B super-voting shares allowed the Sulzberger-Ochs family to maintain an all-but-unchallengeable control of the company while still allowing it to tap the public markets for capital it needed for expansion.

FORBES: Arthur O. Sulzberger, NY Times Publisher and Patriarch, Dead at Age 86

Here is another unchallengeable fact.

FORBES: Forget Market Failure, Our Crumbling Democracy Speaks To Political Failure

His indictment is unchallengeable.

FORBES: Fact and Comment