Haiti demonstrably cannot put down its gangs without external military assistance, and cannot feed its people without substantial external financial and food contributions.
This is clearly a case where the UN needs to step in to establish and maintain stability and safety for Haiti's citizens, possibly via a protectorate or similar mechanism, which could also reduce or prevent the theft and squandering of millions and millions of dollars in foreign aid. Sending in hundreds of social workers rather than soldiers clearly will not bring the violence to an end.
The US or any other country that attempts to solve Haiti's myriad problems unilaterally will inevitably find itself in a lose-lose situation.
If the US were to take the lead in a military effort, Haiti's problems would become the US's problems to solve. This kind of situation is what the UN was founded to deal with; let the UN do its job.
Unfortunately, left to its own devices Haiti seems destined to become the Somalia of the Caribbean.
Haiti is manifestly unable to rule itself. It clearly needs to be ruled with an iron fist, either by a domestic strongman who can crush the gangs and street crime, or by a foreign power that can do the same. Anything else will mean another century of misery and violence.
