The United States may be the world’s sole superpower — but on the soccer field, at least, Americans are still seen as second-tier upstarts.

Which makes it all the more satisfying when the powers of Europe are brought down to size.

The US soccer team Thursday notched a stunning 2-0 upset over mighty Spain in the semifinals of the Confederations Cup in South Africa — one of the main warm-up tournaments ahead of the World Cup there next year.

Spain, the reigning European champion and the top-ranked team worldwide, hadn’t lost in international play since 2006 — a record 35-game streak.

Likely, the Spanish just weren’t expecting much of a fight from the plucky Yanks, who now face Brazil for the championship tomorrow.

Not that this victory necessarily foretells a rise to global dominance for US soccer, of course. It’s a proud mark of American exceptionalism that, here, the sport that commands near-religious devotion elsewhere ranks somewhere between hockey and pro bowling.

But that doesn’t mean there’s anything wrong with beating the world at its own game.

USA! USA! USA!