October 3, 2026: Economic warfare is a strategy warring nations use to weaken an enemy's economy. For thousands of years, this took the form of invading enemy territory and destroying crops and grain reserves. Farming implements were destroyed along with any improvements like irrigation works. Farmers and their families were enslaved, with adult men and teenage boys often slaughtered before they could generate any resistance.

Economic warfare is most apparent in large-scale modern wars. These conflicts include mobilized, well-armed, and well-equipped armies backed by national economies that can keep replacement troops, munitions, weapons, and much else coming to the combat zone. Whichever side can produce these necessities faster has a considerable edge.

This first became apparent in antiquity when the best-prepared armies of spearmen, archers, horsemen, and whatnot prevailed, especially if reinforcements and resupply were available. In ancient times, most armies lived off the land, consuming local food supplies, which often left civilian populations facing famine and dwindling numbers until the next good harvest.

Some 2,500 years ago, the Roman Republic and the later Empire were unstoppable because they paid close attention to supplying their legions. Each of these was the equivalent of a modern combat brigade. About five percent of the armed legionaries had secondary jobs as clerks. They tracked supplies, potential sources of supply, and the status of everything when a legion built a camp after a day’s march. These practices made the Romans immune to surprise attacks on their camps or interruption by an enemy who destroyed all crops and food supplies as they retreated. Such foes were rare, because Rome usually made war on prosperous kingdoms that could be fatally weakened by too much food and crop destruction. Whatever was thrown at them, the Romans were prepared to withstand and deal with.

The Roman Empire eventually fell, at least the Western portion governed from Rome, when Roman forces could no longer use the ancient methods or adapt to new forms of warfare introduced by German invaders. The Eastern Empire, based in Constantinople (Istanbul), lasted another thousand years because the Easterners adapted and sustained the ancient Roman military practices.

Through the 19th century, ancient practices of securing, maintaining, and moving supplies evolved. Most wars and battles took place near waterways, as shipping supplies and troops were most efficient along coasts and up rivers. This was accompanied by another innovation: sailing ships that could handle any kind of weather and carried 40 to 80 cannons. Each cannon had up to 80 cannonballs and powder. These ships could severely damage or destroy enemy waterside port facilities. The warships also captured enemy cargo vessels and added them to their own fleets. Because seaborne trade had become such a vital part of European economies, trading nations needed large fleets and agile diplomats to keep their trade functional and profitable.

This didn’t change, even though an early 20th-century development, the submarine, created a new and more lethal form of economic warfare. World War II subdued the submarine threat through a combination of new technologies and carrier-based anti-submarine aircraft that could cover areas of the Atlantic land-based warplanes could not reach.

At the end of World War II, the United States cut Japan off from essential food supplies from the mainland by deploying naval mines from submarines and long-range bombers. During World War I, large fields of naval mines were used to blockade Germany.

After World War II, it was discovered that economic sanctions didn’t work. The sanctioned nation could always find alternative, more expensive ways to get what it needed. This was, and is, happening recently with Russia. Over four years of economic sanctions because they invaded Ukraine have hurt the Russian economy, but not enough to get the Russian forces out of Ukraine.

The ultimate form of economic warfare is to have a stronger economy. In this respect, the Americans are supreme. The U.S. is not only the largest exporter, accounting for 30% of world trade, but also the world's largest economy. America and its European NATO allies account for nearly half of global GDP.