So much suspicion. You all want the truth? We're planning a surprise attack on the Legion, 4 years from next Thursday, taking place when the moon makes a triangle with Gemini and Orion, and Sirius shines through the middle. Planets will align (even Pluto, just for this occasion), comets will fly past, and every ominous sign will take place within a span of about 30 seconds. Therefore, this treaty has to go. Now be quiet, they'll never suspect a thing with me posting it in public like this (they never believe me anyway, heck, they forgot my birthday. Can you believe that?) but if the rest of you start in, they might get suspicious.
To be serious, though, the reasons are private and were discussed with the Legion. If you can't take a hint, allow me to be slightly more blunt. They are none of your business and will not be shared with you just because you asked, begged, demanded, etc. Please no speculation on the matter, I assure you that most of your guesses would be wrong. As a former Legionnaire, I wish nothing but the best for them, now and into the future.