Yeah, but then there is another perspective as well.
Taking the example of British mainland and their distant colonies all over the world, they actually managed it well, that was all... They didn't have this flawed policy of ours that any attack on a British colony will be countered by an attack from the British mainland.
Therefore, in my personal opinion, it was just bad mismanagement and unequal distribution of resources etc between the two wings which led to disaster... once you denude an area that much, then you are attracting others to fill that vacuum.