For chains that have a broad adoption of validating nodes often called full nodes (check validity of produced blocks but not mining), a 51% attack is not enough

For chains that have a broad adoption of validating nodes often called full nodes (check validity of produced blocks but not mining), a 51% attack is not enough because the bad blocks would not widely propagate. The bad blocks would be ignored. This is why a reasonable size of the state, to allow many many to have affordable nodes which validate and check the rules, is so important. These are not the so-called miners, yet they are critical for the integrity of these distributed systems for preventing nation-state attacks.