Thumbs down, America!

Nothing screams “America” quite like the popularity of “thumbs down guy.”

A New York Mets fan, “thumbs down guy” couldn’t possibly have known he’d be famous thanks to his expressed displeasure about a New York Yankee homerun hit in his team’s stadium — Citi Field — in September.

But famous he is, becoming the symbol for the Yankees and their run to the edge of the World Series.

When the Yankees players do something good — a common occurrence in the postseason this year — down go the thumbs.

His name is Gary Dunaier and he’s become the first New York Mets fan to be loved by Yankees fans.

There are now thumbs-down T-shirts and a thumbs-down bobblehead.

In a conversation with Jimmy Kimmel last night between segments, Dunaier suggested he might root for the Yankees should they make the World Series.