[ U.S. Transportation Secretary Ray LaHood answered several questions in which I attempted to channel the thoughts often expressed by travelers in the D.C. region. Here are the secretary’s response.]

This month, my “On the Go” question-and-answer video features several questions from readers of the Washington Post’s “Dr. Gridlock.” Today, I’m going to answer a few questions from Dr. Gridlock himself. And, although the good doctor’s usual beat covers commuting in the metropolitan Washington region, these are thoughtful questions that easily apply to communities nationwide.

1) Some commuters who identify themselves as drivers, transit users, bikers or walkers, resent government efforts to aid people who travel by methods other than their method. Drivers resent transit projects, bike lanes and pedestrian safety initiatives. Transit users and cyclists resent spending on new highways. As a transportation policy maker, how do you explain to one group of travelers why an expenditure or program is worthwhile if it doesn’t appear to benefit them directly?

This is an easy one: We simply can’t have everyone using the same way of getting around. If we did, our trains and buses would be packed like sardine cans, or our roads would be impassable with congestion, or pedestrians would be overrun by bicyclists.

Investing in transit helps take cars off the road; that actually benefits those who choose to drive or bike. And the plain truth is that people in this country like their cars; I still remember my own first car with more than a little fondness.

The Obama administration has worked hard to help our cars get better gas mileage and operate more cleanly, and so we will continue needing good, well-maintained roads for many years to come. Everywhere I go, people tell me they want more options for getting around, not fewer, and that’s what we’re trying to do.

2) In the Maryland/Virginia/D.C. region, our discussions about tolling highways often generate this question from my readers: Haven’t we already paid for this road? Are they wrong to consider it double taxation if they must pay a new toll to travel a highway that was built with federal tax money?

Tolling is limited on Interstate highways, but the federal programs that do allow states to add tolls require substantial improvements on that particular road. Because the tolling pays for the improvements — but not for building the road — it’s not double taxation.

3) Government, business and civic groups routinely develop lists of transportation projects needed to eliminate congestion over the next 10 or 20 years. But the price tags — in the billions or trillions of dollars — appear to be far beyond what the public is willing to support for congestion relief. Is ending congestion an unrealistic goal for an urban region? (And if so, what’s a more realistic target?) Or are we not being creative enough about finding new sources of revenue to fight congestion?

Look, our population is growing, and we only have so much room. Adding highway lanes is expensive no matter where you do it, and in many places — particularly urban areas — there’s just is no room for more lanes. Some communities are trying to manage congestion with variable pricing on new roads or new HOT [high-occupancy toll] lanes.

Here in our region, you can see that with the Intercounty Connector in Maryland and the toll lanes they’re building on the Beltway in Virginia. The Beltway project is also a public-private partnership, which other communities are looking into as a way to solve funding challenges.

Of course, one less expensive solution to roadway congestion that some urban communities are turning to is more public transit service. The streetcar projects underway here in Washington, D.C., are a terrific example, as is our wildly popular Circulator bus service.

[Besides his monthly “On the Go,” series, LaHood has a blog called Fast Lane, a Twitter feed and a Facebook page .]