Rubuta ci gaba ga wannan sakin layi - A watan Mayu, 1920, an sanya shi a matsayin memba mai kafa kungiyar Matasan Larabawa () ta hanyar gyare-gyaren da masu kafa na asali suka yi wa kundin tsarin jam'iyyar. Matasan Larabawa sun kasance mafi girma kuma mafi rinjaye jam'iyyar Larabawa a ƙarshen zamanin Ottoman da farkon zamanin 'yanci. Ya zama mutum mai tasiri a cikin tawayen Siriya da Faransawa. A cikin 1920 Atassi ya shiga cikin kafa Kwamitin Tsaron Homs, wanda dan uwansa Omar al-Atassi ke jagoranta. Kwamitin ya shirya rikice-rikice tsakanin mutanen Homs da sojojin Faransa. An tuhume shi da bayar da tallafin kuɗi ta hanyar gudummawa daga hukumomin gwamnati da na gwamnati. Tsakanin 1919 da 1925 'yan kishin kasa na Homs sun tura shi don wakiltar su a cikin tarurruka tare da iyalai masu tasiri da kabilu na yankin, kamar Azms, Keilanis da Barazis na Hama, Suweidans na Hisyah, Dandachis na Talkalakh, da kabilar Ahsenah. An gudanar da waɗannan tarurruka don tattauna gwagwarmayar neman 'yancin kai kuma sun kasance farkon juyin juya halin Siriya.
na shekara ta 1925. Ya zama daya daga cikin kwakwalwan da ke bayan tayar da biranen 'yan uwan biyu na Homs da Hama. A cikin 1925 ya shiga Jam'iyyar Jama'a ta Abd al-Rahman Shahbandar, tare da Shukri al-Jundi, Mazhar Raslan, Shafiq al-Husseini, da Abdul-Kareem al-Droubi, kuma suka kafa wani babi a Homs.