They don't really need to prove anything here as it has been known for thousands of years that one of the many ways the people of a land are kept safe is border security. It shouldn't take any sort of great intellect to figure out that if you just let foreigners wonder your lands that your people are at an increased risk.
Any country with borders needs border controls or it won't be a country for long. Ok, sparky, you tell us how the virus got here if not with someone crossing our border. We as a nation have an obligation to protect our nation's borders from invading hordes. We have LEGAL ways to enter this country. Those criminal migrants. who bring nothing with them that justifies letting them in, need to follow the proper procedures.
It’s the usurpation of reason by an incapacity for discriminatory thought on the part of those who are also hoarding food, toilet paper and firearms right now. Part of the MAGA agenda as well. Like Trump’s publicly stated disgruntlement that we can’t get more people from Scandinavian countries coming here as opposed to those from the ‘sh*thole” countries