By 1863-1865, the US had the largest land army in the world with about 2,100,000 men under arms and a 31 ship navy with around 5800 men. While the army was large and battle hardened, the navy only had one ship of the line, the USS Vermont, most were sloops and steamboats. While it was a large army, it was limited to North America because of the small Navy. There was no way to project the power any where other that right around the borders.

At 1860 the Russian army was strongest with 1.2 million. After 1866, the Germans had the strongest at 1.15 million while the US strength drops to about 45000 men. The US kept a small standing army up until WW2 with increases only from 1917 to 1919 for the First World War and the Russian Civil War. Just prior to WW2, the US army was smaller than Portugal's.

Prior to the Civil War, the US had a standing army of less than 30,000 men, with the smallest being 9500 total men in the early 1800's. There were increases from 1813-1816 for the War of 1812 and again in the 1840's for the Mexican American War.