Mexico's presidential frontrunner has proposed providing amnesty to cartel leaders to reduce violence, but the proposal would be virtually impossible to implement. Andres Manuel Lopez Obrador made the proposal -- which would be a significant departure from previous administrations' approaches to security -- during a campaign rally Dec. 2 in Quechultenango, Guerrero state. But it is important to note that the suggestion is just that, a suggestion, and may not translate into actual policy should Lopez Obrador be elected. But even if the candidate does attempt to grant cartel bosses amnesty, a mountain of institutional and logistical obstacles will likely block his efforts....