invulnerable

No sooner has this block of exposition concluded than a cyberattack cripples every system in the U.S.A., including all the ones that had been thought invulnerable.

Progressives tend to split the world into two camps, the vulnerable oppressed and their invulnerable oppressors, which are most determined by your social groups.

And, given their wobbly form, England are certainly not invulnerable to an upset.

Silver lining: King Charles' portrait is invulnerable to Just Stop Oil attacks!

And without it, mice and goats have proved invulnerable when their brains are injected with infectious prion; cattle brain tissue examined in the lab has, too.