Exactly. I love my country and am very proud to be English, I also celebrate St Georges day. Unfortunately, to a lot of people that makes me a racist these days.
That doesn't make you a racist. It's the behaviour of the types that El Pres mentioned that makes it have connotations of racism. There is nothing wrong with national pride but there is everything wrong with negative integration, where people who feel inadequate get false pride by belonging to an abstract collective by actively keeping out certain members of society and discriminating against them.