But the question at hand is whether Trump can slide money from something that's authorized to something that isn't. Congress could have reduced funding for other military spending and authorized it for a "a wall," but it specifically chose not to.
Some folks think that a wall is the most pressing defense issue, I guess, even though billions and billions are already being poured into fortification and more agents.
Some folks think that replacing antiquated and worn-out equipment might matter more to the grunt who's depending on it to save his life on the battlefield.
I agree, that's the question. I think the answer depends on whether or not the military gets to decide exactly what to do with those funds. There's no question a border wall is a defensive barrier. Virtually all national border walls are. So if the military funds are not specifically allocated to specific things, it should be no problem. As long as they are diverted to a national security project, it's all good. But if the funds are allocated to specific projects, specific planes, tanks, carriers, etc., I would think it's a problem.