I think it is fair to say that anyone over 18 and under 65 without a disability and able to work would be considered employable

Even if there were jobs available for every one of them, you wouldn’t have 100% employment in 18-65 non-disabled category. Some people retire early, some people take extended breaks between jobs. 2 out of 5 married women with preschool children are out of labor force.

You really need to break down your millions of unemployed and figure out why they are unemployed and what they are doing instead of working.