It's a big deal because US citizens lost their businesses, their homes, and were shipped off to camps. Did we round up the more numerous citizens of German or Italian extraction?

An interesting side bar to this was that only 2000 of the Japanese in Hawaii, where they made up about a third of the islands' population, were locked up. The US mainland, where the Japanese population was much smaller and constituted less of a threat, was where internment took place
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The Japanese and Chinese population of the West Coast of the US had been facing discrimination and racism for decades before WW 2. That's  the main reason the Japanese were targeted  Anytime US citizens, no matter their race, gender, or religion, have their rights taken away, it's a big deal.