This is a continuing dilemma of New York life: If a stranger’s arm or coat impinges onto your side of an armrest and you do nothing, are you being so big-hearted that you deserve the Presidential Medal of Freedom or are you a wuss?

Permit me to share with you a little-known bit of history that you may find instructive: One day in February 1939, Emil Hacha, the president of Czechoslovakia, was visiting Berlin and popped in to see a movie. Hermann Goering was seated next to Hacha, and a large section of Goering’s bulky Luftwaffe overcoat slopped over their shared armrest. Hacha said nothing. A month later, Germany invaded Czechoslovakia.

I was in a crowded pop-up housewares market in Chelsea last weekend, checking out some repurposed jute washcloths — I just love how they remove the last five years of your face. When I stepped back from the counter I almost tripped over the long handle of a wheelie bag. Not only did the wheelie’s owner not apologize, she snapped at me, saying, “Watch where you’re going!” I was so stunned I just slunk off. By the way, the wheelie owner was not more attractive than I am — that was not a factor. I just did not know how to cope. What should I have done?

What a coincidence! The exact same thing happened to me! I couldn’t come up with anything clever when that entitled shrew told me to watch where I was going, but I did know that most wheelie-luggage people are in poor physical shape. (I mean, did the Terminator come back from the future schlepping a wheelie bag?) So I laughed and, while telling her I would have thought she should be the one paying attention, lightly placed my hand on her shoulder.

Yes, I boldly employed the Laying On of Hands, an aggressive move that anyone fluent in New York body language knows means, “Watch it, sweetheart, or these hands, which have loosened the steely grip of many a top of low-fat peanut butter, will snap your neck like a sidewalk pretzel.”