In 1982, the UK spent 4.5% of gdp on defence, which is more than the 3.9% that the US does now. It sent no troops, and the sum total of its assistance was some missiles and ammunition (which the UK paid for) and access to satalleite intelligence.
The US initially considered stabbing the UK in the back until Caper Weinberger the the Secretary of Defense personally lobbied Reagan to alter his stance of trying to be even handed by pointing out that the UK was a democracy and a much more important ally both strategically and mitsrily that the tinpot military dictatorship that was Argentina. The Royal Navy was also at that time NATOs Premier anti submarine specialidt navy and seeing that fleet decimated would have been hugely damaging for being able to counter Soviet subs going through the GIUK gap and into the Atlantic.
Basically what you have said is bollocks. The US had to be brow eaten into doing the right thing by both Weinberger and Thatcher. It is not something that should have had to be done when the UK was the party that had had its sovereign legal territory attacked.