European Parliament President Martin Schulz recently declared that he was “shocked” by allegations that the United States had planted a bug in the Washington offices of the European Union. German Chancellor Angela Merkel said the news had created “astonishment” in Berlin.

Those reactions recall these immortal words of French Police Captain Louis Renault (played by Claude Rains) as he closes down Rick’s Cafe in the 1942 film classic “Casablanca”: “I am shocked, shocked to find that gambling is going on in this place” — even as a servant hands him his own winnings.

It has been quite a while since President Herbert Hoover’s Secretary of State, Henry Stimson, asserted, “Gentlemen do not read each other’s mail.”

Perhaps Europe’s supposed shock comes from having to admit that when it comes to such uses of U.S. power as electronic snooping (not to mention killer drones), President Barack Obama is no more of a gentleman than harshly criticized predecessor George W. Bush.

As President Obama fairly pointed out: “And I guarantee you that in European capitals, there are people who are interested in, if not what I had for breakfast, at least what my talking points might be should I end up meeting with their leaders. That’s how intelligence services operate.”

At the same time, however, the president promised to look into the situation — a wise effort to mollify his angry European counterparts.

Of course they know that we spy on them and they spy on us. It is the way of governments everywhere.

But it is deeply embarrassing when this secret activity is disclosed in such a blatant manner. And there should be some limits on how much friends — and friendly nations — spy on each other.

Chancellor Merkel predictably ordered her government call in the U.S. ambassador for a formal protest. French President Francois Hollande threatened to cancel U.S trade talks with Europe.

And on Monday, Germany’s government insisted that its cooperation with the U.S. National Security Agency’s intelligence operations have been “strictly legal.”

This flap will most likely blow over in a few weeks. Meanwhile, though, don’t put too much stock in how much European leaders say they are “shocked” by U.S. snooping on them.

After all, like Capt. Renault’s feigned “shocked, shocked” outburst, their expressions of stunned indignation are all part of the show.