From the moment Trump started his presidential campaign, one of his main campaign promises was to fight against Obamacare.

Congress has tried and failed to end Obamacare several times during the Trump presidency. Impatient with Congress' lack of progress, the president has decided to go solo: he's issued an executive order.

According to Vox, the new order doesn't dismantle Obamacare, but it does ease some of the Affordable Care Act's rules, including the option to purchase healthcare outside of the markets created by the law. 

"With these actions, we are moving toward lower costs and more options in the healthcare market and taking crucial steps towards saving the American people from the nightmare of Obamacare," said Trump in an official White House statement.

"We plan to take new measures to provide our people with even more relief and more freedom … this is going to be something that millions and millions of people will be signing up for and they're going to be very happy. This will be great healthcare."

So what exactly does Trump mean by "great health care" and what does his order entail?

Per Bustle, the order calls for federal agencies to develop polices for small businesses to buy what are called "association healthcare plans" (AHPs).

These plans allow for small businesses in the same industry to ban together to buy healthcare for their workers under one umbrella. This is supposed to make healthcare cheaper.

But there's a problem with these plans.

Business collectives can choose which state's insurance rules they when deciding which plans to offer. Some states (like Alabama) have low legal bars for what must be offered in an insurance plan. Business collectives could then save themselves money by setting up an association health plan that follows the state rules of a state that doesn't require much of its plans, even if its employees don't work in that state.

This wouldn't affect healthy people, who would, through the AHPs, pay less than they currently do. But, if any of those healthy people got sick, they would find their coverage of little help to them.

The other issue is that officials fear health people seeking to pay less money per month in insurance bills will jump out of the Obamacare exchanges and into these association healthcare plans.

Again, that's great for them, but the sick people left behind could find their insurance premiums rising. Should enough people leave the Obamacare markets, insurance companies might pull out of them, left with too few customers and too many pay-outs to have an economic incentive to stay. 

Now, if you happen to be sick at the moment, don't worry. The Hill reports that although it still isn't clear how all of this will work, it is clear that to join an AHP “some employer-employee relationship must be present,” meaning that a welder with Obamacare whose company doesn't have an AHP can't just go join the local AHP for vape shops just because it would lower her premiums. 

Another thing the executive order changes is lifting Obamacare's ban on short-term insurance policies. These policies are meant to cover people who have coverage gaps, but aren't subject to Obamacare rules that ensure people with pre-existing conditions can't be denied coverage. 

A senior Trump administration official told CNN that it could take at least six months for the order to come into effect. The order itself doesn't change policy, but mandates that agencies find ways to make its goals a reality.

"The president still firmly believes that Congress must act to repeal and replace Obamacare," Assistant to the President and the Director of the Domestic Policy Council Andrew Bremberg told reporters at the White House. "But before that can be done, this administration must act to provide relief."

Bremberg said the Trump administration expected the policy changes resulting from the president's executive order to "potentially benefit tens of millions of Americans over time."

Of course, critics are worried that this order is essentially undermining Obamacare. New York Senator Chuck Schumer and Kaiser Family Foundation VP Larry Levitt expressed their concerns on Twitter.