Why did the Joint U.S.-U.S.S.R. Commission fail to unify Korea?

The Joint U.S.-U.S.S.R. Commission, established following the Moscow Conference in 1945, failed to unify Korea primarily due to irreconcilable disagreements regarding the consultation of Korean political groups.1

When the commission convened in Seoul in 1946, Soviet delegates demanded the exclusion of any Korean political organizations that had opposed the proposed four-power trusteeship. The United States refused to accept this condition, leading to a deadlock that prevented the commission from making progress toward a unified government. Subsequent meetings held between May and August 1947 also failed to achieve any results, ultimately leading the United States to refer the issue of Korean unification to the United Nations.1