Over the last few weeks, I've spoken with several Mexicans who have expressed shock at the Honduran caravan.  To summarize, they tell me something like this: "What in the world are we doing, inviting caravans to cross Mexico to the U.S.?"

This report from Mexico's southern border with Guatemala suggests an answer:

On the Suchiate River dividing Mexico and Guatemala, it sure looks easy to cross north without papers.

A young, mustached man is pulling a makeshift raft across the quiet river via two ropes connecting the countries. The crossing costs 4 quetzales, 10 pesos or 50 U.S. cents. The raft captain says that nearby migration officials rarely intervene.

But the impression that Mexico is lax on migrants disappears as you head just a little north.

"They put up lots of checkpoints," says Gustavo Rivera, a bus driver shuttling between Mexico's southeastern border and the nearest city, Tapachula. "Immigration [agents], federal police, soldiers, local police. I don't get many migrants on the bus anymore because of the checkpoints."

It sure sounds like Mexico means to stop these northbound caravans.

It makes a lot of sense in many fronts:

1. Mexico has always been harsh on illegal immigration.  Officials see it differently from Mexicans going to the U.S.  There's an economic benefit from illegal immigrants who go to the U.S.: they work and send back remittances.

2. Central Americans have very little to contribute to Mexico.  They are generally poor and would simply compete with Mexico's poor for jobs.  Some may stay in the country and could create problems with Mexicans.

3. Mexico does not want to get the reputation that it is inviting people flow to the U.S.

Mexico's southern border strategy is interesting in another way.  The Mexicans are not flooding the border with soldiers.  Instead, they are using federal agents and checkpoints to do the same thing.  The benefit of this approach is that they don't have to answer questions about militarizing their border at the same time that they oppose the U.S. doing something similar.

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