It amazes me that the tea party faction of the Republican party can simultaneously claim to revere the Constitution and support the government shutdown over the Affordable Care Act.
Consider what has happened. The Affordable Care Act (aka Obamacare) was passed by both houses of Congress and signed by the president. It was then tested in court and declared constitutional by the Supreme Court. It is therefore the law of the land, which the president is constitutionally bound to enforce.
The Constitution provides a way for those who don't like a particular law to change it: they simply have to get a majority of Congress to agree with them and change the law. However, we have a minority group of one house of Congress that wants to make an end run around the Constitution and change a law by bullying the entire country and shutting down the government until they get their way. If they should indeed get their way, our Constitution will be weakened, perhaps fatally.