PORT-AU-PRINCE, Haiti — When the U.S.-backed security force came to Haiti in 2024, Monique Methellus Paul was hopeful.

Kenscoff, the farming town outside Port-au-Prince where Paul lived with her five children, had been spared the heavily armed criminal groups that occupied most of the capital. Now, the 52-year-old vegetable seller believed, the U.N.-approved, Kenyan-led police force “would help push back the gangs” and restore security in this beleaguered Caribbean nation.