Rabbi Akiva

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You must check your facts regarding the dates, because destruction of the Temple was about 60 years before the revolt of Bar Cochva.

You should also study the historical background to the revolt, which includes the Ceasar of Rome building an edifice for idol worship in Israel. Allowing him to continue in such a direction was bringing more and more religious oppression to the Jewish Nation. Therefore, once the revolt took place, surrender would have meant giving in to the religious denial of the message of Israel while still living in Israel. 

See the Rambam that what Rebbe Akiva did was not condered a mistake (Hilchot Melachim 11:4): "And if there will stand a king from the descendents of David [the King]  who learns the Torah and fulfills mitzvot like his father David, according to the Written and Oral Torah, and he will put upon the Jewish People [the responsibility] to go in its ways, and he will fight the wars of Hashem, behold he is to be regarded as [a possible] Mashiach." Only once he passes away does it become clear that he was not Mashiach (Ibid).

With blessings, 
Hidabroot