I live 15 minutes to Brooklyn by car without traffic. I know this may be news to you but NYC is not only the greatest city in the United States, but it's also the most populated. By a large margin. The population is near 9 million. There are people that live here that have come from every state in the nation, including regressive red states. And even if only 20-25% of New Yorkers were Trump supporters, based upon election results, that's still a 2+ million strong general basket of deplorables.
That's a 2+ million pool of suspects. Now if you don't think that within those 2+ million folks there aren't a number of the hardcore racists and scum that Trump has empowered with his rhetoric, then you are a fool. You talk like such a naive uneducated fool. I think that you think that NYC is big, but you really have no fucking clue how big. Because it's liberal NYC it can't be.
Too bad you can't do simple fucking math aka a 2+ million pool of deplorables. The odds are quite high that a sizable number of them, emboldened by a Trump victory, decided to express themselves. It's happening in smaller areas of the country, where the population numbers aren't nearly as high. There are 16 states with a population smaller than just over 2 million.
It can easily happen in Brooklyn.