Dear Left and to some extent the Right,
The United States is in the middle of a very intense battle between Globalism and Nationalism. The thought of Globalism sounds wonderful when it is brought up as a deterrent to future wars, free trade, etc. Riddle me this, who will be in charge, what voice will you have, and who or what will stand up for you? We already live in an environment where those with the most money can manipulate your representatives. The major news sources are owned by a small group. Monopolies are further running amok and the large ones are absorbing those not as large. Imagine how much worse it will be and how much less control you will have over your destiny and potential for happiness.
Globalism will only benefit a very small percentage of humanity. You should be very afraid of this and what it could lead too. To some extent, Globalism is already in place. Just look into the U.S. dollar and see where it takes you.
Diversity is great. Meaning that is okay to be different and have your own personality, culture, likes, and dislikes. We aren't meant to be the same. As Mark Twain once said, "Fences make good neighbors."