Interesting that you bring up the term "melting pot." A lot of people don't know is that prior to 1964, it referred to a melting pot of specifically European cultures, NOT all global cultures. Third world/African/Islamic immigration was not a part of our country back then.
The only outliers in our immigration mix were the Chinese, originally brought here as a labor class, black slaves, and of course Mexicans and South Americans--and of course, the background of most of those countries includes a strong European immigration factor, particularly from Spain.
So, because for centuries the US had only to deal with inter-European culture clashes, which resolved adequately without widespread societal breakdown, we were a remarkably culturally unified and functional country. It helped that the US itself constructed a powerful and very positive, patriotic national identity immigrants could be proud of and aspire to assimilate into.
We also enjoyed a Western European-like degree of safety and comfort in our communities, with precious few disruptive or violent elements. Even our larger cities were safe and civilized for a long time, until unrestricted third world immigration, liberalism and dysfunctional African-American communities began fucking that up. Still, we had a long period of extraordinary contentment and progress. We intend to rebuild that, starting with re-civilizing blacks and fixing culture, and deporting all illegals, crooks, grifters, traitors and parasites.
Multi-culti and globalism directly threaten to destroy all that, FOREVER. You don't need examples if you read here. Some factions make this all about race/skin color, but fundamentally, it's about saving Western culture. We are forging a coalition of groups worldwide that want what we want: our powerful, safe, productive, comfortable, and prosperous societies back. No matter what. Permanently. We will kill or die for this.