BOISE (AP) — Ever since a Democratic-controlled Congress revamped America’s health insurance system in 2010, the notion of government-mandated coverage has vexed most Idaho Republicans.

Thursday’s 5-4 decision by the U.S. Supreme Court to uphold the individual mandate brought cries of protest from conservatives who have railed against the federal law. In 2011, Rep. Vito Barbieri led state efforts to nullify the health care overhaul, with a bill that passed the Idaho House but failed in the Senate on constitutional concerns.

With the justices’ conclusion the mandate is legal, Barbieri believes the decision will renew conservatives’ vigor to block the measure from taking effect in Idaho. Barbieri, of Dalton Gardens in northern Idaho, called the decision “unbelievable.”

“Something is wrong,” Barbieri said. “The state cannot afford this mandate. It’s going to crush Medicaid, it’s going to crush our budget. I will do what I can, to talk to others, to see about at least making a stand that the Supreme Court is wrong, and the state has got to do what it must to protect its finances.”

Two years ago, Barbieri was among the state House’s 49-20 majority in favor of “nullifying” the health care overhaul, using an 18th century states’ rights doctrine promoted by Thomas Jefferson and others, promoting states’ ability to strike down laws that even the Supreme Court upheld.

The Senate State Affairs Committee blocked that measure, saying it violated the U.S. Constitution’s supremacy clause.

But conservatives’ opposition didn’t end there.

During the 2012 Legislature, those same House legislators blocked efforts to create an insurance exchange, an online marketplace for individuals and small businesses to compare and buy insurance that’s part of the Patient Protection and Affordable Care Act’s requirement.

Republicans rejected tapping a $20 million federal grant to create the exchange and also refused alternatively using exclusively state money on a slimmed-down version — over the objections of insurance companies including Blue Cross of Idaho that fear Idaho has been left at the mercy of a federally run exchange where they couldn’t compete.

Idaho Department of Insurance director Bill Deal unsuccessfully promoted the benefits of a state-designed exchange during the session.

The justices’ ruling Thursday reopens the question of how Idaho should respond.

“We’re going to have to take a few days or few weeks to really determine what this decision of the Supreme Court really means,” Deal said. “We’ve got to study, we’ve got to decide, then we’ve got to move forward.”

State Sen. Les Bock, D-Garden City and a lawyer, expects foes of the health insurance exchange to continue their efforts to halt it, but he’s convinced they’ll fail.

That’s because a federal exchange will cover Idaho, even if the state doesn’t put together its own version, as neighboring Oregon is doing now.

“We’re going to hear from them that this is socialism, without offering a solution,” Bock predicted, following the ruling. “Idaho can threaten to not have a health insurance exchange, but then the federal government will provide one.”

In 2010, Gov. C.L. “Butch” Otter signed a law making Idaho the first state to require suing the federal government over the reforms.

On Thursday, Otter was on his annual horseback trail ride with the Idaho Cattle Association and couldn’t be reached for comment on his plans. In a statement, however, his office urged voters to elect a new president and urged federal lawmakers to repeal the law.

“Obamacare has been bad for America from the beginning,” Otter said. “This is a sad day for self-determination and for individual liberty. “

Idaho’s congressional delegation in Washington, D.C., also called for Americans to elect GOP representatives and senators, as well as Republican presidential candidate Mitt Romney, in a bid to repeal the law.

U.S. Rep. Mike Simpson promised the fight isn’t over, and Sen. Mike Crapo told The Associated Press that his party will make the case ahead of November that President Obama is actually raising taxes on the middle class — a sector of the population the Democratic president promised to shield from hikes — by requiring people buy insurance or else face a tax penalty.

Supreme Court Chief Justice John Roberts wrote “the Constitution permits such a tax.”

“It’s an incredible irony right now that the president was able to pass this legislation by claiming it did not raise taxes,” Crapo said. “And yet it was the tax increase that was in the bill that saved the bill in the Supreme Court. Clearly, this decision puts this issue not only back in front of Congress, but also back in front of the American people as we head into the election in November.”

For now, however, Crapo said, Idaho must follow the law.

“The law has been sustained by the Supreme Court, and is enforceable, and we need to recognize that,” said Crapo, who graduated from Harvard Law School two years before Chief Justice Roberts.