A lot of „martial“ skills are needed in daily life. Discipline, planning, ability to operate both on your own and in a team both as a leader and a member. Even physical strength does help, even in modern world. A good CEO and good military commander skillset is very very similar. Just like good specialist and good soldier.

Whenever I meet this phrase, it's talking about specifically those „other kinds of strength“.

I'd even argue that there's no „strength“ in dumbly forcing your will upon others. It's a strength to lead people, to inspire them and get them to follow you. Charisma and leadership is a hell of a strength. But to physically force people... All you need is a number of, possibly weak, people and you'll likely succeed in bending even physically much stronger people.

And weak people banding together can build a tyrant regime. Soviet union is probably good example. Both at initial stage when workers kick started it. And in later stages when usually the weak life scum went to work for the security apparatus of said regime. And reading about other regimes, it seems to be a recurring theme that security apparatus is built out of weak miserable people who look for an revenge opportunity.