WASHINGTON — It was an Old Glory day for New York’s senators yesterday.

Responding to a colleague’s challenge, Sens. Charles Schumer and Kirsten Gillibrand came up with a patriotic way to cover some of the $20 million a year they want for the 9/11 Memorial and Museum: Tax imported American flags.

Sen. Tom Coburn (R-Okla.) had put a hold on the federal money until New York’s two Democrat senators could propose a way to pay for the downtown memorial.

“America has a responsibility to support this national landmark,” Schumer said yesterday.

The funds will ensure “that visitors from across the country and across the world can have inexpensive access to the museum and memorial,” Schumer added.