US President Barack Obama arrives in Mexico today on his first trip to Latin America.The visit is welcome in Mexico, which is at its lowest point since the mid-1990s, plagued by unprecedented criminal violence and a sharply contracting economy. Obama’s trip confirms Washington’s policy change toward Mexico, and in particular the fight against drug cartels. Immigration, and border security are also likely to top the agenda. Moves by Obama to secure hundreds of millions of dollars to help Mexico fight drug trafficking and his acknowledgement that Americans share the blame have prompted Mexico to cooperate in unprecedented ways. The new tone has made it easier for Mexico to welcome increased US border security and even US training for Mexico’s navy. On immigration, Obama is reported to want to revive attempts to reform the law, but on the Mexican side, hopes are low this will happen.