The early Christian church did not fight back against the oppressions of Rome. They were killed by the thousands in gladiator stadiums, torn apart by animals, and crucified for their faith. But they did not resist with arms. They did not fight back with armies or even political campaigns. They fought back with love, forgiveness, and peace. And in less than four hundred years, they defeated one of the strongest empires the world has ever seen.
The Christian church in China did not resist with politics or violence or terrorism while Mao tried to eradicate all Christianity from China. He killed thousands of Chinese Christians in an attempt to wipe them out, but when the restrictions were lifted, the church of 2 million Christians had peacefully grown to 80 million, and the heart of China is now being changed.
The Dutch and Norwegians peacefully resisted Nazi Germany and as a result, far fewer of their Jews were turned over and killed by the Nazi soldiers than those of neighboring countries who fought back.
History is replete with examples of the power of peaceful resistance. It is not an easy path, but there is victory at the end. Either way, people will die, but with pacifism, those who desire peace will not have blood on their hands, and their victory will be a true victory for goodness and justice and mercy. Violent revolutions only end with more violence and a government that is just as oppressive if not more so than the one they replaced because they had to become the enemy to defeat the enemy. Pacifism does not change what it is and so remains pure.
Violence begets violence, and with each death comes more desire for revenge and retribution. I think in the end we would find that far fewer people die as a result of pacifism -- even against the most evil of regimes -- than would have died if a war had been waged.