The possibility of war between the United States and Britain was in the air for years before the War of 1812 actually began, as was the question of whether the United States was ready for war.
Since Republican administrations favored the use of state militias over the formation of a national standing army, the United States Army was not in a position to provide all the soldiers needed. President Madison called for the states to detach a portion of their militia forces for national service, but his call was met with mixed success. Some states were eager to contribute troops, but others, especially in New England, were less enthusiastic about providing men for a war effort they opposed. Reliance on militia presented a number of other problems. Many were poorly equipped, only marginally trained, and in many cases a militiaman’s term of service was only a few months, making it hard to depend on militia on a continuous basis.
Similarly, Republican ideology that favored state power over federal power had slowed the pace of naval construction to a crawl in the decade before the war. Once war became imminent, the government hurried to build a variety of ships that could defend the Atlantic coast, patrol the Great Lakes, and harass British trade. Private vessels also played a role in the war, rarely fighting, but focusing on the pursuit and capture of enemy commercial traffic. This was the last major conflict in which privateers were widely used .