Help: What tech allows amphibious assault?

[unmerged(170751)]

I am playing a unrealistic game here. as Czechoslovakia, took over Italy. I have port now. I also have many TPs. But I noticed I cannot amphibious assualt...so I think I haven't research certain naval doctrine techs yet?

I have only researched the very first 5 core techs in naval doctrine section...Does Fleet-In-Being and Base Strike techs allow amphibious assualt? I asked this because I see that these techs mentioned "max amphibious size:4" so I wonder if it's that?

I am going Sealane Interdiction route in Naval doctrine, would this means I cannot do amphibious assualt ever, if I continue down that route, that is?


Thanks!

 

[unmerged(170751)]

I made a mistake. I just learned that I cannot amphibious assualt if I have a garrison unit on my TPs. Can someone close this thread?

It is my mistake but I learned it. Forgive my stupidity!