The first round of reaction is cautious -- and positive -- about the compromise brokered in the Senate to jettison a "public option" variant in favor of a smorgasbord of increased Medicare eligibility, tighter restrictions on insurers, and a national trigger for some sort of non-profit government-run plan (maybe the same as members of Congress can get).

Indeed, for some health care activists, expanding Medicare has been the primary goal of the entire exercise. It's been a mainstay of Democratic health care proposals since at least Al Gore's presidential run, and its political genesis can be traced to the aftermath of the 1994 Clinton health care failure, when the strategy shifted from "Let's do this all at once" to "Let's cover the kids and those who really need insurance."

What Ezra Klein likes about the Medicare buy-in option is that it provides a mechanism for Medicare to begin to compete with private insurance. He notes that, due to the nature of the way the program is run, its costs and premiums aren't generally known -- and that under this legislation, it'd become quite clear if -- or whether -- Medicare can really provide the same services and quality of services for between 70 and 80% of what it costs a private plan. Still unknown at this point is who is eligible -- and whether, if all the chronically-ill 55-to-64 year olds without access to group insurance plans find their way onto the Medicare rolls, the cost-shifting wouldn't have a deleterious effect on the project of trying to bring down costs overall. Remember, most of those who'd access the "exchange" would be younger and healthier and without insurance -- their premiums subsidizing, in a way, the costs of insuring an older, sicker population. The 55-to-64-year old age group would be eligible to buy into Medicare starting in 2011, but they'd have to do so without premium help until the exchanges kick in -- that's in 2014.

According to TPMDC, "Insurance companies will have the option of creating nationally-based non-profit insurance plans that would offered on the exchanges in every state." If they don't, then the public plan returns, triggered into existence.

BTW: why did a proposed expansion of Medicaid die? Olympia Snowe didn't like it.

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