The Russian five-day blitzkrieg that conquered one-third of Georgia for negligible losses carried a grim warning for the next president of the United States, whether he is John McCain or Barack Obama: Major land wars that could involve U.S. armed forces against formidable opponents are no longer inconceivable.

Only last week Adm. Eduard Baltin of the Russian navy publicly warned that the Russian Black Sea Fleet and its land-based air support assets could sink all U.S. and NATO warships operating in the Black Sea within 20 minutes.

Nor is Russia alone in planning for the possible contingencies of having to fight land wars on a very large scale in different parts of the Eurasian land mass. India and China have come to the same conclusion. Over the past seven years India has bought 657 front-line T-90S Main Battle Tanks from Russia. Russia used less than 10 percent of that number of T-90s in its Georgia operations from Aug. 8-12. The annual production run of the T-90S for the Russian army is only 90 MBTs.

The lessons of what happened in Georgia fly in the face of the Conventional Wisdom complacently assumed by U.S. military planners and most American strategists since the collapse of communism. They have taken for granted the idea that gigantic, full-scale land wars on major continents involving hundreds of thousands or even millions of troops have become inconceivable.

In the 21st century, U.S. policymakers, spearheaded by Donald Rumsfeld during his momentous six-year reign as secretary of defense, have been convinced that the advent of precision weapons, reconnaissance and communications means the United States will remain militarily supreme around the world without needing hundreds of thousands, or even millions, of ground troops to fight large-scale wars.

Republicans, raised in the age of Tom Clancy novels, have lived in a world where this seemed to be true for the past quarter-century. Democrats don't buy into the vision of electronic super-weapons rendering huge masses of less well-equipped troops, cannon and armored vehicles obsolete as enthusiastically as Republicans do, but they still think that the age of massive land confrontations has passed.

That is also the wisdom in every major nation of the European Union, and it's especially the case among European Commission policymakers in Brussels.

The only trouble is that a lot of other major powers around the world do not believe it is true -- and are planning based on very different assumptions.

The Russian army is currently upgrading its equipment on a more massive scale than at any time in at least the past 30 years. It can afford to do this because of the soaring global price of oil and gas, and Russia is the world's largest exporter and revenue earner of those energy sources.

Russia is moving energetically to modernize its army with the latest T-90S Main Battle Tanks, Black Shark tactical support attack helicopters, BMP-90 armored personnel carriers, Multiple Launch Rocket Vehicles and many other systems.

Also, Russia's military leaders, led by tough, politically incorrect, plain-speaking old four-star Chief of the General Staff Gen. Yury Baluyevsky, have been warning over the past two years that future full-scale wars, even including the use of nuclear weapons, are certainly not regarded as inconceivable by their planners.

The Conventional Wisdom in the West, especially in the United States, is that the Soviet and then the Russian army's extremely poor showing in Afghanistan from 1979 to 1987 and then in the two Chechen wars of 1994-96 and 2001-2004 means Russia can be eliminated as a serious factor in land power on the Eurasian land mass.

This is a very different concept from the view popularized by Israeli military historian Martin Van Creveld in "The Transformation of War" -- that large-scale conventional military operations have become outmoded and inconceivable.

Versions of this idea are held, from liberal Democrats who believe, along with Europeans, that economic aid and diplomacy are far more important than raw military power, to neoconservatives who believe that high-tech, precision weapon, state-of-the-art communications technology means the Pentagon can cut 30 tons off the weight of its Main Battle Tanks.

Another view, shared by liberals, neoconservatives and small-government free-traders, is that large production runs on expensive ground weapons like artillery, MBTs or the U.S. Army's HIMARS multiple-launch rocket system are completely unnecessary.

But the armed forces commanders and procurement chiefs of the armies of Russia, India and China don't agree. They have been investing in all those things big time since the 21st century began.

(Part 2: The lessons of Indian, Chinese and Russian arms procurement)