Megan demurs:

A bill with a strong public option looks to me like a bill that can't pass. What am I missing?

That the Reid proposal is a weak public option with state opt-outs? Here's the beauty of it. No one really knows what a public option would ultimately mean. No one really knows what will become of much of these ideas in practice. And that is a real problem for reformers: the unintended consequences could be profound and yet they are also unknowable.

A conservative can say: therefore do nothing. The problem with that is that the status quo is extremely uncomfortable - fiscally and in terms of actual, you know, healthcare. In an insecure economy, it's more than uncomfortable, it's nerve-wracking.

So a conservative can also say: well, let's try it out in a few states and see what happens.

The point of federalism is its abilty to break out of the classic political dilemma: how to change when we are not entirely sure of what change could bring with it? Well: find out. Over time, let's see just how dreadful or helpful a public option is. Let's see if it really does kill off the private sector; let's see if it kills off medical excellence and choice. And let those decisions be made at the most accountable and measurable level: in the states.

It's weird, isn't it, that federalism is becoming an advantage for reform - marriage equality, ending the marijuana prohibition, the public option. But it always was. Conservatism, as I understand it, is not about resisting all change or defending an ideological purity. It's about the least worst, practically relevant solution to emerging problems.

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