When last Friday Russian Ministry of Defense announced that Syrian forces had broken through to the Iraqi border and enveloped the US forces in southern Syria this came as a shock to us here at RI.

Not because this was some move nobody could see coming. Anyone who can read a map could see that a Syrian advance to the east of US positions at al-Tanf base would effectively neutralize it. I spelled out as much a week before the Syrian offensive took place:

The obvious play for the Russian-backed Syrians is to neutralize Americans at al-Tanf by giving their base a 55 kilometer-wide berth and punch through to the Iraqi border further east. Such a maneuver would end US dreams of al-Tanf as a staging point for a push into the Euphrates valley and make it into an irrelevant, isolated outpost in the desert.

No, the shocking part was how quickly the Syrians advanced and with how little warning. Without any previous indication that they intend to do so, the Syrian forces covered 184 kilometers of barren desert in a single day.

It took place so unexpectedly and with such speed that the first we heard about it was when it was all already over — the Syrians were already shaking hands with Iraqis on their joint borders and the Americans had been cut off.

A 184 kilometer march executed in a single day would be a feather in the cap of any force, but is particularly impressive in the Syrian context where advances tend to be far, far slower.

Also, there were no prior announcements or social media rumors that such a move was being prepared — for once the Syrians kept their plans and preparations to themselves.

Additionally, it of was of great help that it took place while all eyes (and American bombs) were focused on much smaller forces testing the US-proclaimed 55 kilometer exclusion zone further east — and which may have been diversionary moves.

We have now learned that the US military was no less shocked by the advance than you and I. Testifying before Congress US Defense Secretary Mattis explained:

“As far as the Tanf situation, that was another operating area that we had. I did not anticipate that the Russians would move there. We knew it was a possibility. I did not anticipate it at that time but it was not a surprise to our intelligence people who saw the potential for them to move out in that direction.”

So then, exactly like RI, the Pentagon saw “the potential” for a Syrian move in that direction (everybody did), but was completely taken aback by how suddenly and quickly it developed.

In military parlance the Syrians did not achieve a “strategic surprise” but they did achieve an “operational surprise”.

In all likelihood US brass could only predict a typical haphazard Syrian advance that would give it plenty of time to react against. Instead it was presented with a fait accompli within a day.

Pentagon grossly underestimated the Syrian forces. Indeed, Mattis had by all appearances convinced himself that Russians were not interested in southern Syria, and that a push to the Iraqi border was a solely Iranian-backed operation with which the Russians disagreed.

In fact, that the Russian Ministry of Defence timed its press briefing for almost the very moment (figuratively speaking) when Syrian and allied forces had reached the border would imply just the opposite was the case.

It also likely means that the Russians contributed heavily to the planning for the operation and that this reflected in its swiftness and professionalism. Indeed, Mattis who speaks of “Russians moving there” now seems to believe so.

Actually he should have known better from the start. Here at RI we always wrote about al-Tanf as ultimately being between the Russians and the US. After all if the Syrians want to restore a land border with Iraq and profit from some of the latter’s manpower reserves that is also in the Russian interest in Syria.

All images in this article are from the author.