The federal government and states such as California are eager to mandate better fuel efficiency in automobiles. These same governments are slow to require themselves, as infrastructure builders, to do much to improve fuel efficiency.

According to federal transportation data, the combined fuel efficiency for various types of automobiles was around 20 mpg in 1970 and near 34 mph today. That’s a 70 percent increase in fuel efficiency that auto makers have achieved in 40 years.

Meanwhile, the road system is just about the same. Sure, there have been changes in technology for road construction — but not much for traffic control.

How could the roads save on fuel efficiency? Easy. Create systems that don’t force drivers to stop as often, particularly pointless stopping.

Who hasn’t had to stop at a stoplight when no one was coming the other from other directions? Many stoplights are on timers, just as they were 40 years ago.

Who hasn’t been the last in a group of cars going down a busy street only to have the light turn so that all of the cars except you continue on?

What if stoplight technology evolved to act more like an actual police officer? An officer can see what’s coming and breaks the traffic at reasonable intervals. Stoplights with sensors only know what is at the junction and have zero input on what is approaching.

It has worked for the government to force Detroit to do better. That has produced results. But it would seem what’s good for the goose is good for the gander. Don’t make Detroit do better without doing better yourself.

Stoplights would be a good start. Not all a once, of course, but whenever new ones are put up, they should be more advanced concerning fuel efficiency of the cars they serve, rather than merely electricity-saving bulbs and lenses.

There are many other ways to reduce unnecessary breaking:

Many four-way stops not in business districts really are just overkill and could be two-way stops. Leave four-way stops for the places they are truly necessary.

It wastes a lot more fuel to stop a two-ton car than to reduce its speed to a slow crawl. That’s why roundabout intersections are much better for fuel efficiency.

Reducing speed limits on freeways, highways and city streets — yes, all three would be very unpopular — would save on fuel when driving, cut down on traffic crashes and reduce the need to brake from higher speeds.

We aren’t necessarily saying the government should do ALL of these things. But some measure of interest in fuel efficiency other mandates for auto makers would be a good gesture on behalf of the government.