Final answer:
Sam Houston advocated for a smaller regular army and the use of Texas Rangers to patrol the frontier to maintain peace and save costs. In contrast, Mirabeau B. Lamar did not follow this policy and instead launched a campaign against Native American tribes in Texas.
Step-by-step explanation:
Decrease in Army Size and Use of Texas Rangers
When comparing the military policies of Sam Houston and Mirabeau B. Lamar, who both played prominent roles during the early years of the Republic of Texas, we find clear distinctions. Sam Houston, the first president of the Lone Star Republic, was in favor of decreasing the size of the regular army and utilizing the Texas Rangers to patrol the Texas frontier. Houston's actions were driven by financial prudence and the desire to maintain peace after the Texas Revolution. In contrast, Lamar, the second president of the Republic of Texas, had a more aggressive stance towards Native American tribes and is not known for decreasing the size of the army in favor of the Rangers. Instead, Lamar's presidency is marked by a campaign of pushing all Native American tribes out of Texas, often referred to as ethnic cleansing.