On Tuesday, I wrote about the shortcomings of Nader-ism, arguing that the achievement of most big-ticket liberal goals depends on a pretty strong, centralized national policy, not the local communities Nader favors. Although it wasn’t among the examples cited in the post, I could have mentioned climate change—since the EPA’s new carbon emissions regulations were released this week, and as the Times reports, the plan “depends heavily on states’ devising individual approaches to meeting goals set in the nation’s capital.” (The paper drily notes that this was also the approach followed in Obamacare, “often with rocky results.”)

Now, the problems of Obamacare’s rocky federalism will not be exactly the same as those faced by the new EPA regulations. One of Obamacare’s features was the choice that states were given to either set up their own exchange or use the federal one. As it turned out, this wasn’t a straightforward “national good, local bad” story: some pro-ACA states (like Kentucky) did a brilliant job running their own exchanges; others (like Oregon) did a miserable job. And the states opposed to the ACA ended up with the federal exchange, which was not exactly a shining moment for government competence. Chief Justice Roberts also inserted some new federalist elements into the law by ruling that states could reject the Medicaid expansion if they chose—a decision that introduced huge new state-level differences in the law’s implementation, and has frustrated one of the law’s main ways of expanding coverage. This map, from the Commonwealth Fund, shows which states took that shameful step, leading to situations like these:

Those excluded will be stranded without insurance, stuck between people with slightly higher incomes who will qualify for federal subsidies on the new health exchanges that went live this week, and those who are poor enough to qualify for Medicaid in its current form, which has income ceilings as low as $11 a day in some states.

People shopping for insurance on the health exchanges are already discovering this bitter twist.

“How can somebody in poverty not be eligible for subsidies?” an unemployed health care worker in Virginia asked through tears. The woman, who identified herself only as Robin L. because she does not want potential employers to know she is down on her luck, thought she had run into a computer problem when she went online Tuesday and learned she would not qualify.

Thankfully, the EPA regulations won’t have exactly that problem: barring some unexpected court ruling, states won’t be able to “opt out” of cutting carbon emissions the way they can now opt out of expanding Medicaid. But there will be a range of differences: states whose economies rely on coal are treated more lightly (West Virginia has to cut its emissions by only 21 percent, whereas Washington must cut its emissions by 84 percent).

There’s some sense in this approach. West Virginia and Washington are very different states, and it’s not clear that a simple one-size-fits-all strategy would be best. But keep in mind that this isn’t a simple binary choice: federalism can be introduced by degrees. In this case, however, the Obama administration didn’t opt for a middle way; its plan, according to one expert quoted in the Times report, is “astounding” in “signaling maximal deference to the states.”

Opting for a flexible, tailored approach is a sensible choice as long as it’s likely to work. This isn’t just a truism: global warming is almost certainly the most important political issue of our era; nothing less than the ability of humans to inhabit huge parts of the earth is at stake. It’s difficult to imagine anything more crucial to get right. A state-level approach will create fifty knock-down drag-out fights over implementation, not just one. Already, conservative governors like Indiana’s Mike Pence are announcing that they will “oppose” the regulations. Others, like Texas’s Rick Perry, are likely to drag their feet and force a showdown with the EPA. Will the federal government be tough enough to ensure meaningful compliance?

Again, if we follow the logic of Croly—who seemed to foresee all of this with astonishing prescience—the states, democratically speaking, have no legitimate complaint about interference by an overweening national government. Once the substance of America’s democratic ideal is set in place, there can no longer be an excuse for local deviations rooted in claims of self-government. That was the lesson Croly took from the 19th-century conflict over slavery. Stephen Douglas, Croly noted, wanted to settle debates over slavery by recourse to popular sovereignty. Douglas defended this idea as the simple requirement of democracy, but according to Croly, once anti-slavery principles had become a part of America’s democratic ideal, local deviations were no longer tolerable. The lesson, as he understood it, applies today too: “no American statesmen,” he concluded, “can hereafter follow Douglas in making the democratic principle equivalent to utter national incoherence and irresponsibility.”