Imagine the United States is an apartment building with a cockroach problem. Some residents, unsettled by the creatures, hire exterminators to end the infestation in their units. Others, however, are ideologically opposed to pesticides, and refuse to take action. In the near-term, a portion of the roaches die off, but in the untreated parts of the building, the colonies multiply. One morning, the guy who paid the exterminator $200 wakes up with a roach on his forehead, and sees several more crawling along the baseboards of his bedroom.