Sen. Marco Rubio (R-Fla.) speaks during a town hall meeting in Pella, Iowa, on Wednesday. (Scott Morgan/Bloomberg News)
Opinion writer

Campaigning for president requires one to come up with policy proposals, a need that from time to time produces innovative and promising ideas. But it also produces some extraordinarily dumb ones, as Marco Rubio is now demonstrating. Here’s his latest plan to fix what’s wrong with Washington:

Shortly after 11 a.m. on the East Coast, Sen. Marco Rubio’s presidential campaign alerted the media to their candidate’s latest position, inspired by the Founding Fathers and by Congress’s seeming inability to pass conservative legislation.

“One of the things I’m going to do on my first day is office is I will put the prestige and power of the presidency behind a constitutional convention of the states,” Rubio said as he campaigned in Iowa. “You know why? Because that is the only way that we are ever going to get term limits on members of Congress or the judiciary and that is the only way we are ever going to get a balanced-budget amendment.”

With this, Rubio manages to combine a promise for something that will never happen with a spectacularly terrible idea.

We’ll start with the constitutional convention. There are two ways an amendment to the Constitution can be proposed: when two-thirds of both houses of Congress vote to do so, or when two-thirds of the states call for a convention to propose amendments. Rubio is saying that because you couldn’t get super-majorities in Congress to support his three ideas, he wants to push for the states to assemble a convention to offer these amendments.

The first thing to understand is that the president has nothing to do with this process. What Rubio is promising is that in between trying to pass his tax cuts and outlaw abortion and repeal Obamacare and wage war on the Islamic State, he’ll use the bully pulpit to advocate for a constitutional convention. So President Rubio will give a speech or two about it? Mention it in the State of the Union? That’s fine, but at best it might bring the chances of getting two-thirds of the states to sign on from approximately zero to ever slightly more than zero. Getting a constitutional convention might be a bit easier than assembling two-thirds majorities in Congress, but not by much.

So he can’t make these constitutional amendments happen. But what about the amendments themselves? Term limits for judges is the only one that might not be all that problematic, but it’s a little hard to tell what the problem is that Rubio is trying to solve. Lifetime tenure for judges is supposed to insulate them from momentary political concerns, but in practice it turns out that there’s plenty of politics on the bench. Presidents pick nominees they hope will reflect their own political values, and most of the time they’re right, with an occasional exception here and there. Some have suggested that the Supreme Court could use more turnover, so there should be a limit of some long but not endless stretch for justices (18 years is one common number). That might be fine, but it’s hard to see what kind of transformation in American justice would result from limiting all federal judges’ terms. If anything, the nominating and confirmation process would become even more political, since you’d need more judges.

But that’s the least bad of these ideas. The next is term limits for Congress, an idea that fell out of favor for a while and Rubio now wants to bring back. But what is it supposed to accomplish? Is Washington going to run more smoothly with more members who don’t know how to pass legislation? We’ve seen a huge influx of new members (mostly Republicans) in the last few congressional elections, and they haven’t exactly been committed to making government work. To the contrary, they’re the ones who care least about having a functioning government and are more likely to be nihilistic extremists who want to shut down the government, default on the national debt and govern by crisis.

Rubio is smart enough to know that the myth of the citizen legislator unsullied by contact with sinister lobbyists, who comes to Washington armed with nothing but common sense and a strong moral fiber and cleans up government, is just that — a myth. But he also knows that saying “Kick all the bums out!” is an easy way to pander to voters’ most simplistic and uninformed impulses.

I’ve saved the worst for last: a balanced-budget amendment. It has long been a popular item on the conservative wish list, but if you put it into practice, it would be an absolute disaster.

The childish way of thinking about it is that a requirement that the government spend no more than it takes in every year would impose fiscal discipline and make government live within its means. But in truth it would require radical cutbacks in everything government does — which means not only the programs Republicans don’t like anyway, but also the ones they do like. In the last half century, through Republican and Democratic presidencies and Republican and Democratic Congresses, we’ve had only five years when the government’s budget was balanced (four of which came during the boom of the Clinton years). Without the ability to issue bonds to cover each year’s shortfall, we’d be left without the ability to do what’s necessary to serve all of our many public needs.

Consider what would happen during an economic downturn if we had a balanced-budget amendment. What you want in that situation is for government to step in and help people — by providing things like food stamps and unemployment compensation to keep people from falling into truly desperate situations of hunger and homelessness, and also to do what it can to spur job creation and keep the recession from being worse than it would otherwise be.

But in a recession, tax revenue also falls, because people are losing jobs and incomes are plummeting; as an example, between 2008 and 2009, the federal government’s revenues declined by more than $400 billion. With a balanced-budget requirement in place, just at the moment when government’s help is needed most, not only would it be powerless to do anything to mitigate the toll of the recession, it also would be required to impose brutal budget cuts, pulling money out of the economy and making things even worse. If Rubio got his way, every recession the country experienced would be deeper, longer and more punishing.

Some conservatives say, “Nearly every state has a balanced-budget amendment, so why can’t the federal government have one too?” But that’s actually another reason why a federal balanced-budget amendment would be so dangerous. When a recession hits, states have no choice but to cut back, slashing needed services and firing workers just when their economies are suffering. At those times, the federal government can step in to limit the damage, boosting the hundreds of billions of dollars it already provides in aid to the states. As it happens, many of the states run by Republicans are the ones most dependent on federal government aid. In 2012, according to the Tax Foundation, the federal government picked up 31.5 percent of all state budgets, including 44 percent of Louisiana’s, 45 percent of Mississippi’s and 41 percent of Tennessee’s. So in places where Republicans are denouncing the federal government in the loudest terms, without the federal government’s help their state finances would utterly collapse.

The good news is that none of what Rubio is advocating for will ever happen. But advocating for constitutional amendments is what you do when you don’t have the stomach for actual governing. It’s certainly seductive — we’ll just change the Constitution, and that will sweep away all the messiness that comes with politics. But it’s a fantasy. Unfortunately, there are still plenty of presidential candidates who don’t respect the voters enough to tell them that passing laws and solving problems is difficult and complicated, and to get what you want to you have to slog your way through it. That’s not an inspiring campaign message, but it’s the truth.