When it comes to gay issues, the world has changed since Chuck Hagel served in the Senate. And among all those gay issues that have shifted over time, change has been perhaps most dramatic in the Pentagon, which executed a 180-degree turn with respect to its culture and policies concerning gay troops. As a result, all future Defense Secretaries will need to address gay issues with the same respect that they bring to all other decisions concerning diversity and military personnel policy. This is particularly true for Chuck Hagel, who has a disturbing, career-long record of staking out anti-gay positions despite his recent support for openly gay service. The standard that he must meet is simple: he must demonstrate the leadership of a 21st-century Defense Secretary by putting his money where his mouth is when it comes to policies concerning gay troops. On gay issues, Chuck Hagel needs to become the most supportive Republican Defense Secretary in American history, a tough standard given the outstanding and inclusive track record of former Secretary Robert Gates. Here are five concrete steps that Hagel should take as Secretary of Defense to prove that his about-face on gay issues is not just talk.