In the awkward aftermath of the Green New Deal's rollout, perhaps the most appropriate question for its supporters, especially the Democratic presidential field, is one often posed by tennis bad boy John McEnroe: "You cannot be serious!"

But, apparently, when New York Rep. Alexandria Ocasio-Cortez and Massachusetts Sen. Edward Markey introduced their proposal in February, they were deadly serious, and breathless progressives couldn't wait to hop aboard the climate change express. First in line, the Democratic presidential candidates in the Senate who were eager to offer up their enthusiastic support.

There was just one snag. The Green New Deal, in reality, wasn't serious. These weren't well-thought-out ideas or vetted policies. They were far left talking points that couldn't possibly survive any real scrutiny. And they didn't.

The blowback was epic. Critics pounced on the resolution's absurd provisions. America would have to retool every structure in the country to maximize energy efficiency. No cars. No planes. Trains to everywhere. Well, except from L.A. to San Francisco, where fiscal reality has already ended that green dream.

But there's more. The Green New Deal goes far beyond a "chicken in every pot." It would turn meat-eating America into a vegan "utopia" with "universal access to healthy food and high-quality health care" for every American, what most of us call socialized medicine.

And last but certainly not least, the Green New Deal would guarantee a job "with a family-sustaining wage, adequate family and medical leave, paid vacations and retirement security" for all.

This is clearly a ridiculous proposal and perhaps Ms. Ocasio-Cortez can learn a lesson from her Green New Deal launch. There is more to legislating than naïve ideas and a lot of wishful thinking, even with a big megaphone.

One person in Washington understands that better than most.

Senate Majority Leader Mitch McConnell sat back and let the Democrats and their presidential candidates climb one by one out on a politically perilous limb called the Green New Deal. He's been around long enough to know the difference between serious policymakers on both sides who want to get something done and politicians who are more comfortable on the campaign trail than in a committee markup.

He also knows the difference between a catchy sound bite and solid policy.

So he decided to call the Democrats' bluff and scheduled a vote on the Green New Deal they had all been touting. For weeks, Democratic presidential candidates had been talking up the climate change issue from Iowa to New Hampshire, as support for the deal was becoming a kind of "litmus test" for many progressive Democratic primary voters. And now there was to be a vote, an actual vote.

Thanks to McConnell, Kamala Harris and Elizabeth Warren would have the opportunity to actually deliver on what had been only pie-in-the-sky promises on climate change. Bernie Sanders and Cory Booker would have a chance to stand tall for bold action and save the planet from climate change. And Amy Klobuchar and Kirsten Gillibrand could now earn their bona fides as relentless climate change warriors.

On March 26, Mitch McConnell gave Democrats the opportunity to stand on principle and vote for the Green New Deal policies they claimed to support. To do their job and legislate.

They whiffed.

All but three Democratic senators voted present, and the Green New Deal went down by a 57-0 vote. It didn't take long for Democrats to realize they'd been had.

They rushed to the microphones to label the lopsided vote a "sham" and with great indignation, defended their non-votes by claiming McConnell had rushed the bill to the floor, outside proper procedure. No hearings, no expert testimony, they complained. No consensus and not enough time. In other words, not enough process, never a very effective argument.

The candidates, still out on that limb, quickly opted for radio silence on the Green New Deal, and turned their focus to crucial issues like packing the Supreme Court, abolishing the Electoral College and giving 16-year-olds the vote. Given the contenders' near unanimity of thought on these and most issues, it's not surprising the primary campaign has since begun to devolve into more of a personality contest than a policy debate.

Their response wasn't to look inward and ponder over the fact that the stumble was theirs. That, perhaps, particularly as presidential candidates, more serious thought should have gone into considering the substance of the Green New Deal rather than rushing to officially embrace a completely unrealistic proposal.

No, their reaction was to blame McConnell for forcing them into an embarrassing position. What they couldn't admit is that the Republican majority leader understood the Green New Deal better than they did.

He understood that, at its essence, the debate about the Green New Deal isn't really between Republicans and Democrats. It's represents a bigger question, whether socialism or capitalism will create a better future for America. Whether this nation wants more government control or values individual freedom. It's a crucial debate that the 2020 election will help settle.

Time to get serious.

David Winston is the president of The Winston Group and a longtime adviser to congressional Republicans. He previously served as the director of planning for Speaker Newt Gingrich. He advises Fortune 100 companies, foundations, and nonprofit organizations on strategic planning and public policy issues, and is an election analyst for CBS News.