How much ocean shipping of troops do we expect, though?

I think there are lots of real concerns about fleet construction, and fleet construction capacity [1]; but if the troop carriers we have work well enough, and we generally airship troops, I don't think we need to be building new ocean going troop carriers with any urgency. As these age out, it may not make sense to replace them.

[1] In WWII, existing shipyards retooled to make warships (as well as replacement cargo ships), and new shipyards were built. In 2025, there are few shipyards in the US and building new shipyards would be challenging... most of the suitable coastal properties are developed.