Obama's Thinking 'Evolves' on Health Care Requirements
PHOTO President Barack Obama sat down for an exclusive interview with ?Good Morning America? anchor Diane Sawyer.

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.

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.

Watch "ABC News Primetime: Questions for the President -- Prescription for America" Wednesday, June 24, at 10 p.m. ET

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.

Obama 'Absolutely' Expects Legislation by Year's End

Obama said he "absolutely" expects to achieve health care reform by the end of this year because he believes the American people share his urgency.

"The reason it's going to get done is because the American people understand it has to get done," Obama said.

To bolster his case, the president painted an ominous picture of what happens if nothing is done.

"If we don't change. If we don't reform the system. Then people are going to lose their health care. Or it's going to take a bigger and bigger chunk of their paycheck. Or their employer is going to start dropping coverage. Or the Federal Government is going to stop -- being able to reimburse everything on Medicare and Medicaid," he said.

Obama said his experiences on the campaign trail and the personal stories Americans share with him solidify his belief that putting off this issue is non-negotiable.

"I travel all across the country and I've done so for the last two years now. Every town I visit, every city I go, people ask me, 'Why is it that my premiums have gone up two, three times in the last nine, 10 years? What can I do when my employer says to me we just can't afford to provide health care anymore?'" he said.

Obama would not consider what it could mean for the rest of his domestic agenda if he does not sign health care legislation this year. Despite recent partisan setbacks on Capitol Hill, the president said he is confident a solution can be achieved.

"We're dealing here in Washington with an enormous federal deficit and debt that is largely driven by health care costs. So whether it's families, business or government, we know that we're going to have to reform this system," he said.

Will Americans Lose a Health Care Plan They Like?

At a White House press conference on Tuesday, Obama seemed to back off from his promise that people who like their health care plans will be able to keep them under his plan for reform.

Instead of saying that "no one" will take away any American's health insurance, Obama said only that the government would not do so, but pinned the possible changes on employers, who may adjust their health care plans due to costs.

"I can guarantee you that there's the possibility for a whole lot of Americans out there that they're not going to end up having the same health care they have," he said Tuesday. "Because what's going to happen is, as costs keep on going up, employers are going to start making decisions: 'We've got to raise premiums on our employees. In some cases, we can't provide health insurance at all.'"

This was a shift from what the president said just last week, when he told a gathering of the nation's doctors, "If you like your doctor, you will be able to keep your doctor, period. If you like your health care plan, you'll be able to keep your health care plan, period. No one will take it away, no matter what."

When pressed by Sawyer on that change in language, Obama again pointed the finger at employers.

"That's the case whether we pass health care or not. The fact is that right now, all across the country, people are losing their health care. Every day," he said.

He said that while Congress cannot pass a law forbidding employers from making changes to their company health care plan, he can say that the government or an employer will not force an individual into the controversial "public option."

"If you're happy with it, and your employer's happy with it, keep it," he said. "If your employer is not providing you the health care that you need, then we're going to give you a set of options to make sure that you continue to have health care."

Obama Defends Public Option

At his Tuesday press conference, Obama defended his wide-ranging health care plan but stopped short of saying that he would veto any plan that does not include the public health insurance option he has been pushing.

"We have not drawn lines in the sand, other than that reform has to control costs and that it has to provide relief to people who don't have health insurance or are under-insured," the president said.

Pressed on the question of whether a public plan is non-negotiable, the president said that it was not, at least not yet.

"You know, those are the broad parameters that we've discussed. There are a whole host of other issues where ultimately I may have a strong opinion, and I will express those to members of Congress as this is shaping up. It's too early to say that," he said. "Right now, I will say that our position is that a public plan makes sense."

The public option system has drawn criticism from both Democrats and Republicans, but Obama refused to say whether it was a necessary element in the legislation that he would sign.

He said it was "not logical" to think that a public option would drive the private insurance industry into the ground.

"If private insurers say that the marketplace provides the best quality health care; if they tell us that they're offering a good deal, then why is it that the government, which they say can't run anything, suddenly is going to drive them out of business? That's not logical," he said.

Obama's Approval Ratings on Health Care Slip

With the health care debate ramping up, with Republicans assailing Democrats for the high price tag and a public option plan, Obama's ratings on the subject slipped slightly in the latest ABC News/Washington Post poll.

Only 53 percent of Americans approve of Obama's handling of health care while 39 percent disapprove of it, up from 29 percent in April, according to the poll.

Obama continues to enjoy high approval ratings, but his policies may not be as popular.

While 65 percent of Americans approve of the president's job performance, less than half of those polled, 47 percent, feel the country is headed in the right direction, making it the first time since Obama's election that views of the country's course have not improved.

More ABC News