After spending over four decades in the Marine Corps and rising to the position of Commander of U.S. Central Command (CENTCOM), James Mattis has been nominated for the position of Secretary of Defense (SecDef) in the cabinet of President-Elect Donald Trump. Known by some in the U.S. Armed Forces as the “most revered Marine in a generation,” Mattis had aided the U.S.’s military dominance overseas through positions such as the Commander of the 1st Marine Division. As its Commander, his unit sustained the longest overland advance in Marine Corps history and catalyzed U.S. victory in the 2003 Battle of Fallujah.

Within a few months of his nomination, Mattis’ candidacy as Secretary of Defense has been cited with concern. President-Elect Trump’s selection of Mattis as SecDef could be vetoed due to the 1947 National Security Act. Signed by Harry S. Truman, the act states that a period of ten years must elapse before a military figure is eligible for the Secretary of Defense. Sixty-one years later, the 2008 National Defense Authorization Act reduced the years removed from active service to seven. Retiring from CENTCOM in 2013, Mattis’ three years of vacant military service does not qualify him to be SecDef according to both acts.

However, there is a solution to Mattis’ predicament of being three years removed from active military service. A waiver can be granted by U.S. lawmakers that can permit Mattis’ candidacy to continue, ignoring the acts’ year restrictions. As a result, the possibility of granting the waiver has generated a whole new issue of Mattis’ ability of civilian control in the U.S. Armed Forces due to his recent military experience. Despite Mattis publicly inquiring that he “recognizes his potential civilian role and how it differs in essence from his former role,” Professor Eliot Cohen of Johns Hopkins University feels that Mattis’ appointment without waiting the seven year period can “pose all kinds of practical problems…  and [it] would make effective leadership of the Department of Defense (DOD) difficult or impossible.

Before Mattis was in consideration for the position of Defense Secretary, his comments of how women cause military units to perform worse created a prevalent controversy in his current candidacy. In 2015, a yearlong study evaluating male and male/female Marine Corps units was released to NPR. The study revealed that male units were 69% more effective in training exercises and were more combat ready than mixed gender units. Due to this new data, the effectiveness of women on the battlefield is back in jeopardy as women have only been able to fight in the U.S. military since 2013, when ex-Secretary of Defense Leon Panetta lifted a ban on women soldiers overseas.

When Mattis was questioned by New York State Senator Kirsten Gillibrand (D) at his confirmation this January, he was asked how he plans to address the issue of women in the military. Instead of alluding to a bipartisan solution, Mattis resorted to inquiries that described his overall military strategy of “the readiness of the [U.S. military] force” with only few mentions of possible rollback for women in the Armed Forces.

If Mattis is sworn in as SecDef, he would be responsible for frameworking the civilian-military relationship in the U.S. through the DOD.  The importance for a civilian-military relationship is to help keep strategic decisions within the civilian political leadership rather than members of the military. As previously viewed in his targeting of women in the military, if Mattis were to discriminate against certain patriotic citizens, it could incense the American public and shatter the civilian-military framework that he is attempting to build.

Due to Mattis’ success as a general, he has gained support from U.S. lawmakers because they feel his military experience can help guide a President with little foreign policy knowledge like Trump to protect the United States from aggression. However for some, it is a concern that Mattis’ three year hiatus from the military is not enough for him to change his view to a policy-based standpoint rather than a general-based standpoint.

The decision for Secretary of Defense is confirmed as of January 12th in which the Senate has bypassed the National Security Act and granted Mattis their vote to be the Secretary of Defense. The vote now proceeds to the House of Representatives to confirm his swearing in. As Mattis’ achievements and flaws have been widely debated, there is little question that his possible position of future Secretary of Defense will hold an influential stake on the United States as the western world continues its drift into global uncertainty.