Obama's Thinking 'Evolves' on Health Care Requirements

Acknowledging that his thinking on the issue has "evolved," President Barack Obama says he could support a law mandating that individuals purchase health care coverage, with fines for those who do not, but he stressed that there must be some kind of waiver for those who are simply unable to afford it.

"People have made some pretty compelling arguments to me that if we want to have a system that drives down costs for everybody, then we've got to have healthier people not opt out of the system," the president said in an exclusive interview with ABC's Diane Sawyer today on "Good Morning America."

During the election campaign, Obama said he was opposed to a federal law mandating the purchase of health care coverage. But earlier this month in a letter to Congressional leaders working on the reform legislation, he said he would consider supporting such a measure, if it has room for exemptions for small businesses and individuals who cannot afford the premiums.

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The president would not delve deeply into the nuts and bolts of what he wants included and what he will concede in health care reform legislation, saying it's still early in the process, but he acknowledged that change will not come easily.

"There's a reason why it hasn't been done for 40-50 years," he said. "It's hard." But Obama once again stressed how urgent he believes it is to tackle this issue and said the cost of inaction is too high.

"If we don't make these decisions, we'll be worse off. If we do make these decisions, are there going to be some difficult changes that we're going to have to go through? Absolutely," he said.

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Obama would not say if he was open to taxing health benefits, but indicated that there was a breaking point in the balance sheets where he would say that the cost of reforming the system is too great for the federal government to handle.

"I think that if any reform that we get is not driving down costs in a serious way ... if people say, 'We're just going to add more people onto a hugely inefficient system,' then I will say no. Because -- we can't afford it," he said.