In a decision with massive political and economic implications, the U.S. Supreme Court has upheld the individual mandate and most of President Obama’s Affordable Care Act.

The decision finds that forcing most Americans to buy health insurance is a tax, and therefore constitutional.

In the ruling, Chief Justice Roberts says:

Nothing in our opinion precludes Congress from offering funds under the ACA to expand the availability of health care, and requiring that states accepting such funds comply with the conditions on their use. What Congress is not free to do is to penalize States that choose not to participate in that new program by taking away their existing Medicaid funding.

A clause in the law regarding Medicaid payments to states was not affirmed, and complicates the impact of the decision.

Marketplace’s John Dimsdale joined us live from Washington following the ruling.

“At least half the states challenged the reform law,” he said, “and if they’re allowed to opt out, that would have the opposite effect on what the individual mandate confirmation would do. Some states may not provide the addition income from the mandated premiums that insurance companies can use to expand health insurance coverage.”

We followed up with some analysis from Frank Newport, editor-in-chief at Gallup.

He was quick to point out that “most polling has shown at least a tilt against the health care act in general,” and that some Americans might not be happy with the results.