In this May 11, 2016 photo, a roving seashell vendor walks past as a street musician serenades a local couple and marines along with local police patrol the shore of Papagayo Beach, in Acapulco, Mexico. Experts say Acapulco shows the limitations of the government’s security strategy. Federal police, almost none of whom are from the city, quickly get lost once they leave the coastal boulevard and ascend into twisting, hillside neighborhoods. Their heavy weapons are ill-suited to urban policing. (AP Photo/Enric Marti)