Why does Hegseth and Trump keep talking about making our military great again, and giving us the strongest military in the world?

Hegseth keeps saying we're going to have the most lethal military, yet we already do? We already have, far and away, the most powerful military on Earth. The US spends almost 5x more than it's closest competitor - China - on our military budget. We have 11 active aircraft carriers - China has 2. We have 750 military bases across 80 countries. We have the most impressive military logistics of any country. The list goes on and on.

So what exactly is the argument that they are making about our military? And how does firing extremely experienced military personnel - like CQ Brown - and replacing him with a retired 3 Star General who says things like "I can take out ISIS in a week" make the military even stronger?