Romney and the individual mandate

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The individual mandate (IM) is the requirement that the individual purchase health care insurance or pay a fine.
Here are the facts as I understand them:
1. Romney's healthcare law in Massachusetts included an individual mandate.
2. Obama's healthcare law contains an individual mandate.
3. There has been a major legal attack on Obama's healthcare law which argues that the individual mandate is unconstitutional.
4. Many people see this as a major problem for Romney.

The argument is that any Rep. candidate must oppose the IM.
Romney cannot oppose the IM because his program contained one.
Therefore Romney has a big problem.

I don't see it.

As everybody (except Nancy Pelosi) knows the Federal Government is limited to its enumerated powers. The states have the power to do anything that is not prohibited to them. That is, the states' powers are open ended.

The IM lawsuit says that the enumerated powers of the Feds as specified in the constitution do not include the power to require an IM.
But the lawsuit does not say that STATES do not have that power.

It seems to me that Romney can simply argue that he believes that this is a legitimate state power but not a federal one.
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