FOR THE PAST generation, the rest of the country has been borrowing Massachusetts’s approach to education policy. This was a win not only for our kids, but for showing all Americans that the result of our Democratic policies are clearly superior to those in red states.

Now, the state’s largest teachers union wants to imperil our schools by copying Illinois’s approach to public finance.

On Beacon Hill, a robust debate is taking place about how to increase funding for all levels of education. Proposals have emerged from the governor, state Senate, and state House of Representatives. There is large agreement on the need to update the state’s formula for distributing aid to districts, and on the need for more funding in general. There are a range of opinions on what proven policies should be expanded and what new models should be piloted.

And for the largest of the discussed amounts – up to $2 billion annually – there are outstanding questions about where the money should come from. There are several responsible options for raising revenue.

And then there is an irresponsible option. Massachusetts Teachers Association president Merrie Najimy has a novel idea as to where new funding could come from: She wants the state to raid its rainy day fund.

“We have a billion dollars in surplus in the rainy-day fund, according to the governor, maybe even more,” Najimy said. “So, there is money that exists to begin the phase-in of full funding of the Foundation budget.”

Politicians have a tendency to be short sighted, looking only up to their last election. Union presidents are politicians, too, as Najimy’s idea demonstrates. They are elected, often by narrow margins (two of the last MTA presidential contests were decided by only two points), and they feel pressure to respond to their constituents’ current concerns.

In recent years, Tea Party-like factions have sprung up within the MTA and created increasing pressure to ramp up the hyperbole. The fad of the moment is to embrace ideas that yield short-term comfort at the expense of long-term sustainability: eliminating testing instead of addressing the inequities it highlights, demonizing non-traditional schools instead of asking why families seek them in the first place, and now seeking funding from untenable sources. Anyone suggesting a more nuanced approach is demonized.

Yet politicians must also be stewards of the future.

At their best, political leaders balance the needs of the moment with their long-term vision in a way that drives successful public policy. It is a credit to our legislative leaders in 1993 and 2010, who made some politically challenging decisions — on management, labor, and progressive local school aid allocations — and in the process ensured that decades later we would still lead the nation. In this pivotal moment for public education, it is crucial that our leaders again respond to the need for immediate change with policies that will reap long-term rewards.

By that metric, the union falls incredibly flat. It is hard to think of any public policy more short-sighted than raiding the rainy day fund.

This is especially bad given that our current rainy day fund is not nearly as robust as it should be. Last October, Moody’s and S&P Global analyzed the Commonwealth’s capacity to weather an economic downturn. Their findings were not promising: We have only enough to fund state government for two weeks.

We’re in the second-longest period of economic expansion since the Federal Reserve started keeping track in 1850. That may blind some short-sighted interest groups to the possibility of a downturn, but for most it is clear that a recession could be just around the corner.

And what gets cut in a recession? Discretionary items, like education.

During the last recession, Massachusetts cut higher education funding by $185 million between FY 2009 and FY 2012. The state was forced to make reduced payments to health care providers. Childcare subsidies were cut by $65 million.

The rainy day fund is meant to fill in these budgetary holes when hard times hit and revenues fall. So the MTA wants us to increase school funding today by eliminating the lifeline for bankrupt schools a few years down the line.

When the rest of the country looks up to Massachusetts in the education rankings, it is not just a win for our students but a win for our model of government. The Democratic Party model of not just big spending but smart spending — major investments paired with accountability against high standards and well-regulated innovation.

We are lucky to have political leaders that reject calls from interest groups to make irresponsible changes to the parts of our system that are working, from high standards and accountability to fostering innovation and making sure our schools survive a rainy day. Our future students cannot afford anything else.

Liam Kerr is director of the Massachusetts state chapter of Democrats for Education Reform.