TR maintained a policy of neutrality with Mexico during their revolution, and any interactions would have been vastly overshadowed by the World War. Like OTL, there were minor border engagements between the two counties, but no manhunt for Pancho Villa. The Mexican Revolution unfolded as it did in our timeline for the most part. On the topic of Pres. Johnson, though direct intervention in the final years of the revolution may be tempting, I believe he would have his hands full with the situation in Canada and domestic unrest. It's fairly likely he would have toyed with the idea of defending Carranza against Zapata, but I would wager Lodge as Secretary of State would have effectively advised against entangling the U.S. in yet another military adventure. The risk would outweigh the rewards, even for TTL's Johnson.How are going things in Mexico? Because with Johnson anxiously looking for a foreign crisis/enemy to keep the nation marching toward his authoritarian anti-Reds leadership that could fill perfectly, especially if Villa e Zapata are winning the Mexican people for their cause.