Mattis is a civilian, he retired in 2013, he would have been eligible in 2020 the way the law is written.
Again, they wrote the law and within 3 years made an exemption for it. And we went 171 years without it really being a problem. Then wrote a law about it that we almost immediately circumvented.
You’re acting like it’s part of Article I or something. It really isn’t. It’s just a wonky rule that didn’t really do anything. Our nation was less militaristic before it even existed, so obviously it didn’t mean much of anything as far as keeping the military under civilian oversight.
Consider this: if it hadn’t been Mattis here were some of our potential choices:
Mike Flynn - a Russian agent and insane person who worships Trump like a God. Thinks Muslims are inhuman cancer
Tom Cotton - who basically wanted to go to war with Iran and is a prime Trump boot-licker
Jeff Session - he ended up being AG. A racist hobgoblin who would drown babies if Trump told him to.
I could go on, but every person Trump would have nominated would be loyal to Trump, not the nation or the Constitution. Because that’s what Trump’s people are like. But hey they’re civilians so that would be better!
The “tradition” is a new one that got an exemption almost the moment it started and is circumvented by 7 years as a civvie. Pretty sure in 3 years Mattis will still be the person he is right now.
Anyway, I’m done. But I seriously don’t get your angle. In the extreme abstract I sort of do, but our first President was literally a general and at the end of the day the President is all that matters and he is a civilian. The only reason Sec of Defense matters is because Trump is an idiot and doesn’t give a shit about what the military is doing as long as they drop a bomb on something when he tells them to. Crap like Sessions/DeVos is a far bigger deal.