Critical to any military success is logistics or the ability of a military force to move troops quickly without interruption and with more than adequate supplies for their purposes. There are numerous examples in military history where the inability to supply the troops with necessary amounts of food, water, and clothing resulted in defeat in a battle. In military history, not being able to provide the military is usually a prelude to the end of the war, surrender, or outright defeat. The Spanish American War is an example.
Although we often think of the Spanish American War as one grand battle in Cuba, the fight with Spain took place in other countries around the world. Fighting in Cuba began in June with the critical campaign for Cuba on July 1. However, earlier battles started in the Philippines in May. In Manila, the Spanish fleet was unprepared, and the American fleet destroyed much of the Spanish Navy, leaving the Spanish without the means of transport critical supplies to other battlefronts. Some historians claim that Spain, by the time of the war, was a declining world power struggling to maintain its preeminence as a naval power. The defeat at the hands of the less experienced American Navy was proof of the Spanish decline.
In Santiago de Cuba, the Spanish fleet was ordered to abandon their positions and leave the port immediately by Spanish military leaders. Some historians think the Spanish thought if they left Cuba, war with the United States could be avoided and a remnant of the fleet would continue to operate. The fleet leaving had dramatic consequences to the battle for Cuba. Spanish troops put up a valiant fight on land. El Caney and San Juan were the sites of the bloodiest fighting for both sides. Within a few days, the toll on Spanish troops and having their supplies as well as reinforcements cut off effectively demoralized the Spanish troops and resulted in surrender. On July 17, the Spanish decided to concede Cuba to the Americans ending the war.
Historians debate whether the war would have ended as quickly if the Spanish were able to re-supply their troops in Cuba. However, if the lessons in military history are any guide, not having reliable supply lines most always ends in defeat.