Of course a cheaper peso gives the US greater leverage over Mexico. Mexico is the annual recipient of $26 billion in remittances from the US. The amount exceeds the sale of oil to the US. We can attach a surcharge to the remittances. Also, if Mexico wants to engage in a trade war with the US, it would be the bigger loser.
Wait until the illegal aliens from Mexico start flooding back to Mexico. It happened in a more limited amount when AZ passed its e-verify law (upheld by SCOTUS). The Mexican mayors along the border met with AZ legislators telling them the influx of their citizens from the US was causing havoc in their communities.
Mexico Is Angry Mexican legislators expressed concern that an Arizona law would prompt an influx of Mexicans into Sonora from Arizona