日本国とアメリカ合衆国との間の相互協力及び安全保障条約
Etō was a very prolific author, and his books and essays ranged from literary criticism and to postwar political commentary; through taking controversial viewpoints, he also established himself as one of foremost public intellectuals in the print and television. He was initially a prominent member of the movement against the Treaty of Mutual Cooperation and Security between the United States and Japan, establishing the "Young Japan Society" with like-minded writers and intellectuals, although he later reversed his position after a revised version of the treaty was ratified, accusing his former colleagues of "intellectual bankruptcy" and of confusing politics with morality.