The former commanders for Central and European Command have been named top advisers for a Washington D.C.-based national security think tank.
Joining nearly 150 former U.S. general and flag officers on the council, Stavridis and Zinni will lead the organization's efforts to link American military power to U.S. diplomacy to advance national security objectives around the world.
"Even when military power is unavoidable, our development and diplomacy initiatives are essential to keeping the peace and helping nations get back on their feet after conflict subsides,” Zinni said in a statement Wednesday.
“Without those tools, it’s all too likely that the forces of chaos and insecurity will take over again," the former four-star general said.
During his time at Southern Command and later European Command, Stavridis saw "firsthand how the tools of development assistance and diplomacy often help nations around the globe stabilize and prosper,” he said. "As they do, they create the conditions that can defuse conflict before it requires a military response."
Since leaving the Pentagon, Stavridis has openly questioned the benefits of U.S. military action, particularly in areas like Syria, warning it could lead to a prolonged U.S. intervention in the country that could cost U.S. lives.
"One strike is a very different proposition than launching a big campaign," according to the former four-star admiral who oversaw the American and NATO military intervention in Libya.
"The benefit of surprise and stealth and a single-point strike may or may not tell us a good deal about Syrian air defense," Stavridis cautioned in an interview in May.
The best thing Washington and its allies can do in Syria is to keep the war from bleeding over into Turkey, a NATO ally, he added.
"NATO has to protect the NATO border. We have to ensure that Turkey is secure and that this doesn't spill into the Turkey border," Stavridis added.