If the UK was actually more interested in ties with the rest of Europe than its ties with the US, I'd agree.
I think you're correct but for other reasons than the one you suggest.
The UK is closer culturally to Australia, Canada, New Zealand and to a lesser extent the US than a lot of places in Europe. This is also particularly true legally where we're probably the only EU country (except Malta?) to use Common Law.
There were economic reasons for joining the EEC when we did but I wonder if things would have gone smoother had we pursued a union of equals with our former Dominions.