The Republic of Texas spearheaded the American involvement in ending the drug wars. Arizona, New Mexico, and the California Republics had their own parts of course, but the Texas Guard threw the greatest weight of weapons and men at the problem. They were the largest military in America short of the national armed forces, and would have ranked in the top ten list of world militaries on their own before the Second Great Depression began. So their command of the border situation became natural when the federal government collapsed.