Military - As introduced, prohibits the Tennessee national guard, or a member of the national guard, from being released from state duty into federal active duty combat unless the United States congress has passed an official declaration of war or has taken an official action pursuant to Article 1, Section 8, Clause 15, of the United States Constitution to explicitly call forth the Tennessee national guard or a member of the national guard for the enumerated purposes to expressly execute the laws of the union, repel an invasion, or suppress an insurrection. - Amends TCA Title 58, Chapter 1.

SB 156 prohibits Tennessee National Guard members from being deployed to federal active duty combat unless the U.S. Congress has declared war or taken specific action under the Constitution (Article I, Section 8, Clause 15) to call them for executing federal laws, repelling invasion, or suppressing insurrection. It defines "active duty combat" as participating in armed conflict, performing hazardous duty in foreign states, or using "instrumentality of war." The bill allows the governor to still deploy Guard members under Title 32 for domestic civil support missions within the U.S. and territories. This directly affects all Tennessee National Guard members and requires the governor to ensure compliance with the new restriction.