Overall economic performance: Notice California is well above average, and Kansas is well below.

Golden State voters elected a Democratic governor, Jerry Brown, and elected huge Democratic majorities. The state’s budget was in shambles when Brown took over from Republican Arnold Schwarzenegger, with a deficit of $25 billion in fiscal year 2011-12.

What did Democrats do?

They raised taxes on the wealthiest households, and their plan brought the budget into balance, paid down huge debts from past deficits, and has even run surpluses the last couple of years. At the same time, California’s economic growth rate has been very strong. In the most recent year for which we have data, it was more than double the average for the country, and was in fact tied for the highest rate with Oregon—another state with a Democratic governor and Democratic majorities in both houses of the state legislature. California may have to make some adjustments going forward, but overall the liberal tax and budget policies implemented a few years ago have been a real success.

Now let’s get back to what happened this week in Kansas.

The budget situation finally got so desperate that the Republican-controlled state legislature voted to essentially undo the Brownback tax cuts. Since they took effect, state revenues have cratered, Kansas has already had to raise taxes twice before to cover the shortfall, and the state has enacted significant, painful cuts to education, infrastructure, and just about everything else.

What did Brownback do? He vetoed the measure, and although the House voted (by one vote) to override, the state Senate sustained his veto, falling three votes short of an override—although two more senators voted for override than voted for the initial bill. Bear in mind that Republicans control 70 percent of the seats in the legislature, so even this result is a strong repudiation of a failed policy. The governor’s alternative plan, according to the Wichita Eagle, “would primarily rely on sources of one-time money to get the state through 2019.” In other words, it’s a bunch of gimmicks.

The point of the ‘Kansas Experiment’ was to find out if trickle-down really worked. At the time of its passage, Brownback proclaimed: “We believe this is a strategy that builds a strong state in the future on the red-state model.” Mitch McConnell admitted, “This is exactly the sort of thing we want to do here, in Washington, but can’t, at least for now.” Arthur Laffer (yes, the Laffer Curve guy) and Stephen Moore, who advised Brownback on the tax cuts, had predicted that they would have a “near immediate and permanent” positive impact.

Just 18 months in, when the deleterious effects were already apparent, Moore said: “It’s a little early to tell about Kansas.” Yeah, right. In a 2014 piece defending the cuts, Moore got the data so badly wrong that he was forced to publish a correction. The editor of the paper that published the initial article declared that she’d never publish anything by him again. Moore served as an economic advisor to the Trump campaign, and has offered similarly rosy predictions about the tax proposals the campaign put forth. Doesn’t that put your mind at ease?

Rather than get the data wrong, Brownback simply ordered the Kansas Council of Economic Advisors—brought into being by the governor himself—to stop issuing reports on the state’s economic performance. Whether that’s better than just issuing alternative economic facts is debatable.

What have we learned from all this? Well, it depends on which “we" you’re talking about. Here’s Kevin Drum:

[Kansas] has caused conservatives to think long and hard about their contention that cutting taxes on the rich and slashing bloated budgets will supercharge the economy. Haha. Just kidding. What they’ve actually done is either (a) ignore Kansas or (b) spend lots of time trying to dig up reasons that Kansas is a special case and would have done even worse if Brownback hadn’t stepped in. These reasons tend to be pretty ridiculous, but so far they’ve been good enough to keep the rubes in line. And that’s what matters, right?

Last June I wrote a post arguing that, although it was important to attack Trump, “every Democrat should run against the GOP meltdown in Kansas.” That’s even more true today. Democrats have a real argument to make. We can point to actual performance to show that our plans work better in real time for the American people than our opponents’ plans.

Their plans lead to disaster, and Kansas is Exhibit A. Democrats must use it to put Republicans across the country, including popular vote loser Donald Trump, on the defensive. We must demand that they account for the failure of the right-wing Kansas Experiment. Democrats should hammer McConnell on whether—now that his party can implement whatever tax policy it wants—he still wants to do to America what conservatives did to Kansas. Ask him—and every Republican—why liberal California did the opposite, and got much better results.

Are facts and figures as much fun as a early morning tweet from a president like this?

x Yes, Arnold Schwarzenegger did a really bad job as Governor of California and even worse on the Apprentice...but at least he tried hard! — Donald J. Trump (@realDonaldTrump) February 3, 2017

Maybe not. But Democrats need to show the American people that governing is about results, about delivering for them. And liberal policies do that a hell of a lot better than conservative ones.

Ian Reifowitz is the author of Obama’s America: A Transformative Vision of Our National Identity (Potomac Books).