How did Panama gain independence from Colombia in 1903?

Panama gained its independence from Colombia in 1903 following the Colombian senate's rejection of the Hay–Herrán Treaty, which had been negotiated to allow the United States to construct a canal across the Isthmus of Panama.12

Seeking to secure the canal project, the U.S. government actively supported a Panamanian secessionist movement. With the tacit approval of the United States and the strategic presence of the U.S. Navy in nearby waters, Panama declared its independence on November 3, 1903. The United States granted de facto recognition to the new republic just three days later.231

Following this separation, the two nations signed the Hay–Bunau-Varilla Treaty. This agreement guaranteed Panama's independence while granting the United States exclusive, perpetual control over the Canal Zone for the construction and operation of the Panama Canal.12