Disagree with you there. Dubai is perfectly situated for Indians flying to Europe/NA, Far East Asians to Africa, Aussies to Europe, North Americans to Africa, Europeans to Asia/Afica/India, and of course Gulf Residents to anywhere. IST would require some backtracking for quite a few of those groups. Not to mention the IST airport is a mess and Turkish appears to be chronically mis-managed. Don't see much of a threat there.
The reality is that the biggest threat to EK is a lack of slots and local restrictions. The protectionist response shows that many don't have a competitive response. If Europe becomes saturated then they will send more capacity to North America and Asia. Do you think the US will block EK with a pending order for 200+ 777X's in the balance? How many billions does that represent?
The only saving grace for US legacies is that most of the business travelers in the US are tied to a frequent flyer program. The big threat to DAL will be once EK starts flying to the west coast via Asia and the east coast via Europe.
I disagree with your disagree.

)) Anyway, Turk has a hub closer to Europe, and actually can legally fly to ANYWHERE in Europe, and they do. If you look at their map, they have A321s to almost every large European city, when the ME airlines are still restricted. They also have different sized planes, that can hit every market. EK has the A330 as the smallest plane, and EY and QR have A320s. Yes, FlyDubai is an offshoot of EK and they use 738s, but they really don't go anywhere in Continental Europe. So, Turk has a huge advantage, and they use big planes too to SE Asia and Asia itself, along with many cities all over Africa. They fly flights to Mogidishu, to Dontsk, to Bamako, to Goteborg. They are the ones to watch out for when it comes to European airlines and protecting their own turf, they have NO ROADBLOCKS, whereas the ME airlines do. From IST they also have 777-300s to LAX, ORD, IAH, JFK, IAD (maybe an A330), and maybe MIA also. But for US carriers, will people overfly Europe (to IST) to fly back to Europe (LHR, CDG, etc)? Probably not. But connection traffic to almost everywhere else is a possibility.
As far as EK flying from MXP to JFK, I doubt many other European countries will allow that (protecting their own first), and Italy right now is on the ropes financially, so maybe there is something going on with politics and ME money. You never know....
As far as EK flying from the West Coast to Asia, I don't think that is a certainty. They would have to get the rights, and those particular countries also protect their own (Japan is very careful with HND slots etc), and it's already been done, called Singapore Airlines. They have FANTASTIC service with "Singapore Girls", flying from NRT to LAX, ICN and TPE to SFO, and onward towards SIN. That doesn't seem to bother the US legacies much.
Bye Bye---General Lee