Let’s be accurate here. The vast majority of those of Japanese descent were not interned, they were relocated. The practical effect was pretty much the same but legally they could live outside the camps if they had a place to go. Most did not. Some were released from camps to attend school or join the military.
You make a very important distinction.
From one perspective, American boys and fathers were being killed in a desperate war by "relatives" of the very Japanese that were walking around on U.S. streets. Those Japanese were easily distinguished from the larger community and, while not often mentioned, faced substantial risk of physical injury.
While a comfortable relocation was warranted, IMO the real tragedy was that many Japanese suffered an enormous economic loss that could have been avoided.
I also believe the author is over the top with his assertion the internment "... was arguably the worst violation of civil liberties in this country’s history". Is he discounting our earlier use of slavery?