The political and military seeds for war were sewn long before he was imprisoned following the Moncada barracks debacle in 1953. At the time guerrilla warfare was virtually unknown, yet Fidel and his group had to devise a plan that would take a small band of poorly armed civilians and defeat an 80,000 man well-armed military backed by the world's biggest superpower. The charge was daunting, yet they forged ahead during those years leading up to their 1956 attack looking for any and all advantages over their vastly superior enemy. They knew that only through the added help of the local citizenry did they ever hope to win against Batista.
Their plan included attacking their enemy at its weakest, using Mother Nature wherever possible. If Batista's army was 400 strong, they'd wait until they were marching single-file before attacking. If the army was in armored trucks, they'd use land mines to destroy their vehicles. Once the army surrendered, they would take them prisoner, treat the wounded and leave them with medical care if they couldn't be moved. Fidel and his group knew that by treating their enemy with internationally recognized rules of war they would be winning the battle a second time and making it easier for future combatants to give up knowing that they would be well treated. As the war raged on, Batista's forces continued to burn homes, kill innocent civilians and destroy farms of suspected rebel sympathizers. It soon became obvious that the strategy of treating army and civilians with respect and dignity was clearly winning over the oft-used government tactic of terrorism and torture.
By treating the enemy with respect, avoiding violence, torture and intimidation at all turns, tending to the wounded and infirm from both sides and ensuring that the civilian population was always properly recompensed for their services, Fidel made it possible for his group to win the hearts and minds of not only the civilians across the island, but of the very same army they were fighting. Where Batista used the ancient tactics of terror, torture, death and destruction to intimidate everyone they found in their path, the revolutionary forces commanded by Fidel followed international law and respected soldier and civilian alike. The only point where the death penalty became necessary was when members of his own forces were caught stealing from the local citizenry and were condemned under the rules of combat inside of a war zone. No case of prisoner mistreatment from that war has ever been leveled against Fidel and his forces in the fifty years since he assumed power.
The revolutionary war fought by his small, poorly armed civilians supplied more with ideology than weaponry shows how powerful the respect for the rule of law and the proper treatment of mankind can be when used to defeat terror, torture and mistreatment. Batista only knew violence and that was all he was shown from his American backers. His powers proved far inferior when matched against the rights of man and the respect and dignity of mankind. Had free speech the right of assembly been available to the people of Cuba at the time, it's even possible that the whole war and subsequent bloodshed could have been avoided entirely.