Alan,
Having known Simon for quite some time, I know for a fact that he is not anti-American.
What he is, IMHO, is anti-anything that he sees as having an adverse or unfair effect on others.
This does, again IMHO, make him anti-establishment in that he deplores the negative effect of some big businesses. He also deplores spin-doctor type politics as typified by Blair & Bush. Plus he loathes the harmful effects of pollution on our Earth.
The US is always going to be the worst offender in most of these areas, partly because of its size and partly because it's slow to implement greener policies, possibly due to the pressures imposed by big business.
Personally, I like to consider many of the benefits that the US has given the world, which, IMHO (again!) does much to redress at least some of the balance against the negative points.
On the other hand, I too would get quite pissy if someone continually criticised my own countries policies over-much, even if they did keep telling me how much they liked English people.
It's OK for me to criticise them BTW, but when foreigners do it, you'd better watch out!
Englishman.