I am a nationalist why is that bad? Western culture is something to be proud of and Europe is rich with culture and history America has many different mixes and blends of culture depending on where you are why should any of that be dulled to not offend people? if they don't like it they can go away.
The reason I despise nationalism, in all its forms, is because it is almost exclusively used as a way to elevate "Us" over "Them", based on location of birth, Race, and sometimes culture. These are things most poeple have no control over, the fact you happened to be born somewhere should not factor into your politics or self worth. If the only thing that matters to you about who you are is your nation, bluntly, either your a soldier or you have a problem. The divisive nature of nationalism also makes it very easy for nationalists to stop viewng Foreigners as people, and thats when things get DANGEROUS.
Your country's job, at its core, is to regulate trade (Making sure you are buying what you think you are buying), maintain a code of laws (Making sure you don't get murdered), and to keep you safe from invading forces (Making sure you don't get murdered). Some governments also make it their job to keep you healthy and happy, but that varies between nations. Your nation IS NOT special, it IS NOT worthy of special praise, and if you think it is, it won't be next time the president/king/prime-minister changes.
As for the land, its a lump of mud and rock, and some of it is damp. Wow, so impressive. Tell me more about your glorious dirt and stones.
Having said that, I have no problem with people showing off harmless culture, culture is intresting and cool and as long as it does not involve sacrificing virgins to volcano's or something if you enjoy embracing your culture, more power to you. Equally if you want to embrace someone elses culture, do so!
As for global warming, most people yelling about it are actually super scared (As am I). We may be looking at the end of the world as we know it in our lifetimes, it should not be suprising some people are freaking out and going a bit crazy.
Racism goes both ways, but in most nations that are fighting racism, racism against black people is vastly more common and damaging. Society as a whole is more racist towards blacks, and while individals can be dickheads, racism agianst white people is not part of the wests overall culture, so ultimately its less vital to fight it (Also a lot of it is reactionary, "you are racist towards us, so we will be racist back." Fighting this directly risks making it more prevelent.)
Multiculturism as a whole is a necessary part of humanities growth IMO. Segregating views and beliefs will end badly in a connected world. We need dialog, and we also need to see eachother as people. that is the ONLY way forward for humanity as a society and culture.
Then again, thats just what I think. Maybe everyone else completely disagrees.