Final answer:
The United States recognized the independence of Panama and signed the Hay-Bunau-Varilla Treaty in 1903, gaining control of the Panama Canal.
Step-by-step explanation:
The United States recognized the independence of Panama and signed the Hay-Bunau-Varilla Treaty in 1903. This treaty stated that the United States would have "use, occupation and control" of a 10 mile-wide canal zone "in perpetuity" and would pay $250,000 a year to Panama for it.