The protectionism was/is there in the US too. I unfortunately can't remember the details but there is a video in the Computer History Museum that tells a story about how computers from Germany were blocked in the US and the impact it had on both countries.

And just last year the US blocked Qualcomm being sold to a Chinese company: https://qz.com/1227509/trump-just-blocked-broadcoms-attempt-...

Of course, as the US now has a extraordinarily strong advantage in the sector it doesn't have to flex that muscle as often. But it does flex it when needed.