...after 9-11, 828 people [have been tried] on terrorism charges in civilian courts. At the time of publication of this excellent report from the Center on Law and Security, NYU School of Law last year, trials were still pending against 235 of those folks. That leaves 593 resolved indictments, of which 523 were convicted of some crime, for a conviction rate of 88%.
With regard to military tribunals, the Bush administration inaugurated 20 such cases. So far just three convictions have been won.
So in traditional criminal courts, the backbone of our constitutional system, 88% conviction rate. In the allegedly AWESOME military tribunals 15%.
But as always in conservative arguments the lesser solution is the "right" choice not because of the facts but because it sounds more 'badass'.
It's pretty much the totality of all current talking points from the Republican Party.