Islamic State is said to have shifted a considerable amount of its military assets from the Syrian theater to Iraq in order to achieve victory in Ramadi. The militant group was able to do so because it faces relatively little resistance in Syria, mostly because other outfits such as the Army of Conquest (which includes Ahrar al-Sham and the al-Nusra Front) have scored a string of victories against al-Assad’s increasingly exhausted and demoralized armed forces.

This movement saw ISIS troops being shifted southward through its ‘capital’ of Raqqa and along the Euphrates River into Iraq:

Then past the Al-Qaim border crossing (captured by ISIS in June 2014) and continuing along the Euphrates all the way to Ramadi:

Now what remains to be seen is whether or not ISIS can consolidate its hold on the area between Ramadi and its longtime stronghold of Fallujah. Doing so is complicated by the fact that there are not only two major roads and a highway linking Ramadi and Fallujah, but also a road linking Ramadi with the government-held city of Samarra to the northwest. This leaves ISIS forces susceptible to a two-pronged government counterattack.