The result was primarily decided on a military level

The answer is obvious: The Asia Minor Campaign was primarily decided on a military level. Diplomacy (as an instrument of politics) played its part. It overturned the secret agreements over the partition of the Ottoman Empire and the zones of influence between the Great Powers that were forged during the First World War. Diplomacy allowed the disembarkation of the Hellenic Army in Smyrna in 1919 to restore order. It granted the administration of Smyrna and the surrounding area to Greece for five years with the Treaty of Sevres, after which sovereignty over the region could have been granted to Greece by a decision of the League of Nations and the agreement of the local legislative body. It founded a state for the Armenians in the eastern territories of Asia Minor.

But (a big BUT) the implementation of the Treaty of Sevres depended on the military defeat of Kemal. In the beginning, the Young Turk movement, which later developed into the Kemal movement, was not particularly popular with the Muslim population of Asia Minor. The situation changed following the arrival of the Hellenic Army in Smyrna. The majority of Turks sided with Kemal and reinforced his ranks. Thus, the forces of Kemal were in a position to challenge the provisions of the Treaty of Sevres despite facing the French in Cilicia, the British near the straits, the Armenians to the east, the Italians on the Asia Minor coast facing the Dodecanese (Caria and Lycia), and the Greeks in Ionia.

The real question is which of these allied nations were willing to implement the Treaty of Sevres against the Kemalist forces. The states with interests in the area were Great Britain, France, Italy and Greece. The Armenians, a potential Greek ally, did not have their own state and found themselves fighting both the Turks and Soviets alone and were defeated by the end of 1920.

The three Great Powers had been exhausted by the battles of the First World War. Their war dead numbered 750,000 soldiers for Great Britain, 1,350,000 for the French, and 460,000 Italians. Their societies demanded the immediate discharge of troops and the return of reservists to their homes, and not the continuation of bloody hostilities in the lands of the Ottoman Empire. Additionally, there began an Anglo-French competition over control of the Near and Middle East. It was clear that Greece was part of the British sphere of influence. This made France treat Greece with suspicion. The situation was exacerbated following armed clashes between the French and the Kemalists in the region of Cilicia. The French were convinced that continued hostilities would be a particularly bloody affair and preferred to find a settlement with Kemal to sacrificing more lives. On the other hand, Italy was convinced that it had been treated unjustly with the signing of the Treaty of Sevres. In fact, Italy considered that Greece, which was seen as a direct competitor, had been favored at its expense. As a result, Italy adopted a clearly anti-Greek stance. This meant that Greece found itself alone in imposing the provisions of the Sevres Treaty on the Ottoman Empire and this could only be achieved through the use of arms. The return of King Constantine after the elections of November 1920 made the situation on the battlefield for the Greeks much worse. France (a sworn enemy of Constantine) and Italy had the perfect excuse to distance themselves from the Treaty of Sevres, which they utilized. It began with France surrendering its heavy armaments in Cilicia to Kemal. Italy also provided refuge to groups of Kemalists that were being pursued by the Greek forces. Starting in October 1921, French and Italian merchant ships (that is allied ships, which could not be searched by the Hellenic Navy) began transporting military equipment to Kemal through the ports of Mersin and Antalya (protected by France and Italy respectively).

Moreover, starting from March 1921 the Kemalists were also supported by the Soviet Union. The Soviets saw in Turkey an anti-imperialist movement that was fighting the two main capitalist powers in Europe: Great Britain and France. Soviet aid took the form of millions of gold rubles and more importantly, arms and ammunition.

Through these extremely difficult conditions, Greece fought alone while also experiencing the National Schism. The Allies made diplomatic efforts to find a solution from 1920 through to the end of the Asia Minor Campaign. They just confirmed that the Treaty of Sevres was going to be revised. The extent of this revision was defined by the collapse of the Hellenic Army in August 1922 and, unfortunately, the crushing defeat.