In 66, 115, and 132 there were 3 large Jewish revolts against the Roman empire and they all ended disastrously. The rabbis and students who were left holding the pieces of Jewish society realized that if not done right, Jewish revolts were not worth the risk to the continuity of society/torah study. Although some Talmud rabbis, such as Rabbi Akiva, supported the Bar Kochba revolt, the depiction of Bar Kochba and the Zealots who wanted war with the Romans during the first revolt, is strongly negative.
FYI, According to wikipedia, there was another revolt in 351, Samaritan revolts in the 5th and 6th centuries, and a Jewish-Persian action that led to a short lived Jewish province that was recaptured by the Byzantines. Caliph Omar had Jewish support when he conquered Palestine from the Byzantines in 637.