Found something better. About halfway down this page is a photograph of a Japanese ship in San Diego Bay in 1911. They were supposedly scouting for an invasion of Baja California scheduled for April, 1915.
Smart move! Up to the 1770s there was no US presence in the Americas, from then on it continually increased! Snapping right into action, after only 141 years Japan responds!
I tried to do a Lexis search but I don’t think it goes back that far. The LA Times’ online archieve only goes back to 1986. I don’t know if the my Universities library will have the LA Times back that far, but I will try to check this weekend.
I have access to the historic LA Times and other papers through ProQuest. There are numerous stories about the Turtle Bay incident in all the major papers.
You can pretty much read any major paper from April 14, 1915 on for information.
I didn’t get a chance to look for microfilm of the LA Times story. However, even if that story was listed accurately, it does not mean that the Japan had a secret treaty with Mexico. I would like to throw this out to someone with better research Kung-Fu (Cecil I’m looking at you) than me.