Roland Purfew
As I've already stated, the RAF capabilities the US supposedly considered 'essential' amount to about 20 aircraft in total, all of them old to ancient. In any event, I think we all realise the US could have done without the RAF's contribution completely if necessary.
What you and Climbear seem to be saying is that the RAF has certain niche capabilities that the US finds useful. In which case, why don't we invest in these capabilities instead of wasting billions on 232 Typhoon?