The hardest part is making the chips, no? Packaging facilities cost ~20% of a fab, right? Naively, I'm assuming packaging is also not as complicate and diffic

The hardest part is making the chips, no? Packaging facilities cost ~20% of a fab, right? Naively, I'm assuming packaging is also not as complicate and difficult as fabrication. Surely if they can build a fab in the US, they can build packaging facilities, too. Rome wasn't built in a day.