You forget that the Jews were given the choice to free Barrabas, the political savior, from the death penalty, or to free Jesus, and they chose Barrabas. Once Jesus made it clear that His revolution did not come by changing the government, He lost His thousands and remained with only a handful of followers. It was with His resurrection that His followers began to understand and return to belief in His way. (Which did in fact conquer Rome without a drop of Roman blood being shed within a mere two and a half centuries).
Those Christians in today's society that seek political power to impose Christian values are doing nothing more than screaming "Barrabas!" once again, and leaving the Savior to be crucified. They are the Jews sacrificing their true Savior for a chance to overthrow Rome. But our duty is and always will be to humbly spread the good news and let the Holy Spirit deal with the results.