I agree, with one stipulation. As someone who legally carries a concealed weapon and frequently returns from the range to carry several locked cases from my car to my door, I get annoyed when I hear stories of people panicking, just because of the presence of a weapon. I always take care to be cheerful, so as not to scare people, but at the same time I take a great deal of care to ensure that my weapon is NEVER visible at all, and there are some places I don't take it, even when perfectly legal, just because I don't think it's appropriate. Apparently this happened close to a few recent violent events, one of which involved a sword.

Do I think he has a right to have the umbrella in public? Absolutely. Do I think he should exercise a bit more discretion considering the circumstances? Yes. But there was some serious overreacting here, either by the person who reported it, or the police.

edit: My university has recently had several occurrences of 'alleged' gun sightings (that turned out to be cell phones), and each time the police has responded with one or two armed officers to investigate the situation. A measured, but conservative response.