The very short version: United HealthCare is the biggest health care insurance provider in the country (something like 70 million people, apparently). It is huge, it is influential, it is weighty. And UHC took a $425 million dollar haircut last year in the Obamacare exchanges, so now it’s thinking of stopping selling on the exchange by the end of next year. Note that UHC did not say that they would, merely that they might. They did this at a shareholders’ meeting, too; which suggests that a large part of that might have been due to UHC’s awareness that people were...