A letter sent to President George W. Bush last month urges the president to push for more fuel-efficient vehicles, to increased development of renewable energy sources and to begin a serious effort to reduce the United States' dependence on foreign oil.

The ideas expressed in the letter are nothing new. Left-leaning environmentalists and so-called tree huggers and have been pushing this message for years.

But this time, the message is coming from the right - and from people in the national security, intelligence and military communities.

The well-publicized letter to Bush was signed by leading members of recent administrations including, Robert McFarlane, former Reagan national security adviser; former CIA director James Woolsey; C. Boyden Gray, former adviser to President George H. W. Bush; and Frank Gaffney, a former Reagan administration official who now heads Center for Security Policy, a Washington think tank.

Rather than approaching the United States' foreign oil dependence from an environmental perspective, these former administration officials focus more on national security and economic concerns.

As members of the Energy Future Coalition, the signers of the letter ask Bush to work to raise the mileage standards (CAFE) for cars and trucks and to shift attention away from increased domestic oil production and toward development of renewable energy alternatives. The group notes that even with expanded oil drilling in Alaska (including the controversial ANWR), the U.S. cannot satisfy its current or future oil thirst from domestic sources.

By relying on imported oil to fuel 60 percent of the United States' oil needs, this country is at great risk - both economically and militarily - according to Woolsey, MacFarlane and the other letter signers. Volatile Middle East politics and the very real potential for terrorist attacks that could interrupt the flow of oil to the U.S. are only the most obvious risks facing the U.S.

Surging global demand for oil (in addition to steel and other raw materials) due to China's need to fuel its rapidly growing economy, will also threaten U.S. economic and national security interests. China's developing military might and economic power could lead to confrontations with the United States over securing oil sources around the world.

All of these risks can be minimized if the United States begins to reduce its dependence on imported oil by rapidly increasing the fuel efficiency of cars and trucks on the roads and by accelerating the development of alternative, renewable energy sources.

Given America's great agricultural resources, the full potential of bio-diesel fuel should be explored as should the improved economics of ethanol. Further, McFarlane and the other letter signers note in the Wall Street Journal, hybrid vehicles that can be plugged in for recharging of their batteries at night, when electricity costs are low, equates to filling those cars' fuel tanks with 50 cents-a-gallon gasoline.

The Bush administration's mindset (reflected in the energy bill recently passed by the House of Representatives) to emphasize mostly more oil production is status-quo thinking that can no longer be defended.

The stature and bi-partisan mix of the signers of this letter should cause more people to sit up and take notice.

The benefits of reducing the reliance of the U.S. on imported oil has near-universal acceptance. How to do it remains the subject of ongoing debate.

Given the economic and national security risks facing the U.S., it is foolish and perhaps dangerous to resist efforts to mandate increased fuel efficiency for cars and trucks and to put serious federal support behind the development of renewable energy sources.