Why were Vietnam-wide elections planned for 1956 never held?

The nationwide elections scheduled for 1956 to reunify Vietnam were never held primarily because the South Vietnamese government, led by Ngo Dinh Diem, and the United States refused to participate in them.123

The Geneva Accords of 1954, which established a temporary partition of the country at the 17th parallel, included a Final Declaration calling for these elections to be supervised by an international commission. However, because the Viet Minh were widely expected to win, the U.S. government and the South Vietnamese leadership declined to sign or approve the declaration.124

Diem, who had consolidated power in the South and established the Republic of Vietnam, publicly opposed the elections. With American support, he refused to participate, effectively preventing the vote from taking place. This refusal was a key factor in the subsequent escalation of conflict, as the North Vietnamese government and communist-led forces, known as the Viet Cong, eventually launched an insurgency to reunify the country by force.56134