In my opinion, I believe that this is not a politicized issue. The United States government does not just hand out free rations of money to Mexico. This is not an EL AL/Israel case. The U.S. does provide Mexico with assistance and funding in certain issues such as the drug war, but Mexico's economy is pretty much dependent on how well the economy of the United States is doing. If the U.S. economy catches a cold; Mexico catches the flu, so therefore it important for the Mexican economy to have a robust American economy. However, AeroMexico's best interest is to get the best price per plane, and it is the job of each aircraft manufacturer to bid and offer the most competitive deal to win the order.
AeroMexico has been traditionally a loyal Boeing/Douglas customer, but business is business and what matters is the bottom line. There has been strong rumors that suggest that one of the reasons why AeroMexico is more inclined to Boeing has to do with influece from its close partner Delta Airlines, who might just one day (in the not too distant future) be the owner of AeroMexico.
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