So, apparently it took 12 legions, literally half of the regular force, to put down the Bar Kokhba revolt. What the hell made a bunch of desert jews so tough?
But they didn't have "that many dudes", sending that much force to Judea left the border stripped up by the Danube; and while nothing slipped through at the time, it was a pretty nasty risk to take.
Not to mention the expense in shipping troops halfway across the empire. Generally, the Emperors wanted to keep the troops where they were if at all possible.
There is a quote i love, "The jews are the only enemy you a legionaire will face who will stab you, then sue you as soon as you turn around." Basically it wasnt just the rebels, it was everyone fighting the romans, a jewish total war. They were also just super fanatical
The "Great revolt" was 66-70, not in 63.
And I don't know, it seemed pretty necessary. Hadrian broke the tradition of saying "I and the Legions are well" when formally writing to the Senate over the revolt, and Legio XXII was wiped out, with IX and X pretty badly mauled.