Baja California Peninsula sealed off from Mexico Proper

Fenestella

Banned
If the US were determined to annex the Baja California Peninsula in the 19th or early 20th century, where would they maneuver to seal off the Peninsula from Mexico Proper most rapidly and effectively?
From Yuma to the Colorado River Delta?
Once sealed off, how quickly would it fall?
 
The easiest would be run the Arizona border straight west to the Sea of Cortez giving the Arizona territory a coastline and a Port.

The Baja Peninsula is beautiful but desolate without the rainfall to support large scale agriculture the only reason to annex it would be during the whaling period as the Gray whales head to Laguna San Ignacio breed.
 
Top