Couple of interesting observations from the comments:
I'll only add one other supporting piece of evidence that the ISIS escapes were allowed to happen on purpose by the SDF. Note that they (or more precisely, CENTCOM) has started their scorched-earth total destruction of central Raqqa before they closed the southern border. There are surprisingly few Kurdish casualties (relatively speaking) for the current assault - a sure sign that they are herding civilians and ISIS with Marine artillery and aerial bombardment rather than with ground assaults. Makes me wonder what the Arabs from Raqqa are thinking as they watch their city leveled and burnt to the ground to 'save' it, all while CENTCOM herds ISIS to Palmyra or Deir EzZor for more havoc.
Posted by: PavewayIV | Jun 14, 2017 3:06:07 PM
One other possible reason for holding Tanf, has to do with oil. After Erdogans juicy side-line of "exporting" "ISIS" oil into Turkey, was shut down by the Russians a couple of years ago, it was mentioned that there was still a supply line "to Jordan". (It was not clear exactly where this passed.)
If you google-earth "Tanf" there are several large objects that look tankers at the Tanf crossing. (Google is politically biaised and may "change" the photos)
So, the road through Tanf leads up to the Al Busairi Junction (4-ways), where one road goes to Damascus, one other north and the third goes towards Palmyra, BUT south of the mountains. (The Syrian Gov, attack being along the north of the same mountain range.) This last road would have enabled tankers to circumvent Palmyra and go directly to ISIS held oil wells. (A bit of cross- country desert couls also be imagined)
In other words, By holding Tanf, the US, UK and Norewegians were deliberately permitting a supply line to and from ISIS. Oil one way and arms the other?
The Gov. now has control of the Busairi crossing and a much bigger area around Palmyra, thus cutting ISIS off.
End line of the oil route would have been Jordan and probably Tel Aviv.
Posted by: stonebird | Jun 14, 2017 10:47:55 AM