Who says U.S. can't do big things again?

The United States used to do things big. It built a highway system to connect a nation and advance economic development. It built vast airports connecting it to the world. It even sent men to the moon and returned them safely to Earth.

But now much of that highway infrastructure is in need of rebuilding or expanding. Many of the nation's airports leave visitors from other parts of the world wondering about our failure to modernize. And while sending an unmanned vehicle to continue exploration of Mars was a remarkable achievement, it fails to excite the populace as did human space explorers.

Sometimes it seems like the country has lost its ability to go big. Faced with historically high deficits and Republican aversion to raising anyone's taxes, it would seem the nation just can't afford it. But maintaining and modernizing the nation's infrastructure is critical to economic growth, both through the construction jobs it creates and the long-term opportunities it presents.

That is why the Amtrak proposal to build a bullet train along the Northeast Corridor from Washington to Boston should be greeted with excitement, not dismissed as unrealistic. The current passenger rail routes between the major cities on the corridor run along the coast. These are where the major population centers were found as rail developed, the places where the cargo from the sea hooked up with transportation systems on the land.

But it is a terrible system if the goal is to build a fast train. The tracks twist and turn with the curves of the shoreline. They encounter numerous draw bridges that must be opened and closed to accommodate sea traffic. They squeeze through neighborhoods and cities.

The bullet train proposal calls for building a rail line inland, cutting diagonally across Connecticut, for instance, without big curves, allowing trains to travel at 220 mph. An express train could travel from Boston to New York in about 90 minutes, from Philadelphia to New York in under 40 minutes. One particularly ambitious concept calls for building an 18-mile train tunnel beneath Long Island Sound.

A viable high-speed rail system would provide an alternative to air flight. It would get commuters out of cars. And it would encourage economic development along the corridor because of its ability to move large numbers of people quickly.

Yes the challenges are monumental and the potential pitfalls significant. Price estimates range from $100 billion to $200 billion (a lot, but far less than the $700 billion TARP bailout). Amtrak talks about service starting around 2040. Initial proposals have the bullet trains flying non-stop through Connecticut, right through Hartford. That won't do.

And the impact on coastal cities, including New London, would need to be evaluated. The preliminary plans call for leaving in place the existing 457-mile Northeast Corridor route running along the shoreline. It would provide cheaper service to travelers not in such a hurry and with business or pleasure planned in coastal cities. The traditional Amtrak corridor would also connect with the bullet train at key points.

Is this far fetched? It shouldn't be. Other nations do it. Evaluating the concept proposals, the Federal Railroad Administration is undertaking a three-year study of what high-speed rail in the Northeast should look like. The nation can benefit by dreaming big again.