Why is that?
Correct me if I am wrong but Delta currently operates only one non-stop between these markets (to IAD). Is there really that much traffic on a day-to-day basis to sustain two non-stops?
Ladevale, there are actually two daily SLC-IAD nonstops, one 757, and one 737-8. Both run consistenly full, and as with all SLC-East Coast flights, Delta carries an enormous amount of connection traffic from the Rocky Mountain and Pacific Coast regions. I'm certain Delta won't find it difficult to run the flights full and profitable.
I imagine the new flight will replace the late morning SLC-IAD flight.
As for your argument about the decision being political, it's clear that 9 out of every 10 DOT decisions are almost purely political. Somebody with your level of intelligence and knowledge should know that the AA-BA issue is that 1 out of 10. The stakes are simply too high.
It's a new day. Every moment matters. Now, more than ever.