Competition lacking among private health insurers

One of the most widely accepted arguments against a government medical plan for the middle class is that it would quash competition—just what private insurers seem to be doing themselves in many parts of the U.S. Several studies show that in lots of places, one or two companies dominate the market. For Democrats, the answer is a public plan that would compete with private insurers. Republicans see that as a government power grab. President Barack Obama looks to be trapped in the middle of an argument that could sink his effort to overhaul the healthcare system.