"Soccer" is an English word derived from "association football," their term for play-by-the-rules "footy." In the early life of the game, rowdy Englishmen's play led to an association establishing the rules of play (How British).
Despite their WWII alliance with Stalin, Brits aren't commies. They're socialists (the BBC, the NHS, et al). "Soccer" is a perfectly "Brit" term.
North Americans having once known the yolk of Their Majesties (along with the Aussies) use the term, "soccer," because they have developed their own games of football. Snotty Brits scoff at these, characterizing them as perversions of rugby - "They only use their bloody feet when they can't do anything else! They shouldn't be allowed to call it 'football!'"
So, if you wish to display your derision of soccer, couch it in terms of our successful revolution, the victories of the war of 1812, and our saving their effete asses in WWII. Britain owes the US its very existence.
As far as their game, futbol may have spread worldwide because all one needs is a ball and a field on which to play. Don't let them forget that England hasn't won the World Cup since 1966.
*Disclaimer: Having broken my left forearm while in Pop Warner football practice, my parents declared that was it for me and football. I took up the game of soccer and played it intermittently into my 30s. Of course, I undertook other sports as well - beerball (rec league softball), volleyball, and, eventually, skydiving.