Startupboy points out an interesting idea: Securitize Citizenship. In other words, give every US citizen a blank passport, and let them do whatever they want with it. This is a great idea! It solves several problems. First, it allows people who don't like immigrants to buy up passports and destroy them. Second, because there will certainly be a market for purchasing these passports, it lets all US citizens benefit from their hard work in making the US a nice place to live. Third, because the price will change, it will give citizens a personal reason to increase the quality of their government as seen by the rest of the world.