Political. The Europeans didn't want US companies selling
sets there.

Didn't stop the Japanese, etc. But US companies would have
to do other mods to their products for European sales anyway.
Like mains voltage and frequency. Most couldn't be bothered --
even when that's all which had to be changed.

I don't buy that. US sets would have been fairly expensive in Europe, even
in the mid-60s. Not to mention the strong competition from Thomson, Philips,
etc.