Kinocker,
I disagree entirely with your assertion that Aer Lingus expansion eastward was hopeless. They tried it as did Gulf air in the peak of booming Ireland.
They didn't have a clear strategic link for seamless travel through Dubai. Besides the airlines of the Emirates have the resources and scale to make it work where other's did not.
Putting a focus on the core and profitable markets ie the U.S. was the right choice and they have made substantial profess to date.