The immediate demand for trained workers, brought about by the low unemployment rate, hides an even better reason for the Legislature to support a proposal to expand Maine’s technical college system. When the strong national economy recedes, as it inevitably will, the states with the best-trained labor force will feel the slowdown the least. If Maine can’t afford to protect itself now against such a day, it never can.

L.D. 686 funds the recommendations of a task force on employment needs for high-tech companies. It would spend $1 million during each of the next two years to expand the programs at the colleges to serve emerging industries such as sensor development, composite-materials manufacturing and bioscience technology. As Maine’s mills continue to downsize, these industries will become known as the good-job fields of the next decade or so — good pay, benefits, an opportunity for advancement. The kind of jobs Maine hires consultants to try to attract to the state.

But the companies that offer these jobs won’t come or expand here if the workforce is not present to allow it. The Maine Economic Growth Council last year found that 69 percent of employers had trouble in the preceding 12 months finding skilled workers. When House Speaker Steven Rowe last week called for support to expand the technical colleges, he brought along a list of 191 Maine businesses statewide that need but have yet to find 2,200 skilled employees. The technical colleges are a prime source for these workers, but they could do far more.

Three legislative commissions in recent years have recommended doubling the enrollment size of the state’s seven technical colleges, from 5,300 to 10,000. A shortage of money has meant that Maine throughout this decade has passed up a chance to train thousands of residents for high-wage jobs. But now is an excellent time to invest both in programs and the bricks and mortar needed to accommodate more students.

Even during these relatively prosperous times of rock-bottom unemployment rates, the technical colleges receive far more applications for admissions than they can accept. That’s because workers without skills will still find plenty of work — but at low-end service jobs. These jobs can be a good place to start a working life, but they’re tough spots from which to try to raise a family. And they can easily disappear during a recession, leaving both families and the social services to support them out of luck.

Expanding the technical-college system is one of the best ways to raise Maine’s dismal income ranking of 37th among states. It can help spur development and improve the quality of life for thousands of residents. Especially in times of surplus, when lawmakers can do all that for the state, they ought to jump at the chance.