I come from a tradition of military service. My parents served full careers in the Navy. My grandfather served a career that included fighter missions during World War II; my grandmother served as a Navy nurse. I served four years as a naval officer, and my brother, Army Captain Nathan Smith, currently serves at command headquarters in Kuwait in the battle against the Islamic State. Military service is something that my family has never taken lightly.

Last week, Nathan sued President Obama, asking the federal courts to declare the war against ISIS illegal because Congress has failed to authorize it. He came to this decision only after intensive soul-searching and research, some of which I have been privy to over the past year. When Nathan got to Kuwait, it became clear to him within a few months that this was a very different situation than his previous deployment to Afghanistan in 2013. He began calling me when he could and was soon expressing serious concern over the level of escalation and the fact that there seemed to be no end in sight to mission creep. He increasingly began to reflect on the meaning of his officer's oath to "support and defend the Constitution of the United States against all enemies, foreign and domestic" -- an oath that did not demand obedience to the commander-in-chief, but to the Constitution.

Our constitutional system of checks and balances safeguards the country against two evils -- military dictatorship on one hand, autocracy on the other. It establishes a symbiotic relationship in which both the military and the political system rely on one another to carry out a complementary set of responsibilities. Our elected politicians depend on the military to carry out the actions necessary to safeguard the country's interests. The military, in turn, depends on elected representatives to ensure their directed actions comply with the Constitution. Such is our democracy.

This system breaks down when the political system fails to carry out its responsibility concerning the military's mission. Our Constitution and the War Powers Act of 1973 make it quite clear that the President cannot deploy troops longer than 90 days without the authorization of Congress, no matter how morally justified the cause may be. We have now been fighting ISIS for almost two years, with no end in sight. The President's justification for this intervention is Congress' authorization for a war in Afghanistan in response to 9/11. But ISIS didn't exist at that time, and the current war is not in Afghanistan.

This puts conscientious military members in a very difficult situation: the President's order to fight an unauthorized war requires them to violate their oath to "support and uphold the Constitution," which by extension requires them to disobey orders that are unconstitutional. Herein lies the crux of Nathan's case.

If our politicians believe the conflict against ISIS is important enough for people like Master Sergeant Joshua Wheeler, Staff Sergeant Louis Cardin, and Petty Officer 1st Class Charlie Keating to die for, then it is time for them to step up to the plate and authorize the war. What it is not time to do is to expect military members to unquestioningly follow orders that violate their oath to the Constitution simply because the political process is difficult and unwieldy. Members of the military put their lives at risk every day to perform the missions handed to them by politicians. The least politicians can do is approve these missions as required by law.

But if it is Congress that must authorize the war, why is Nathan suing the President rather than Congress? After all, President Obama has proposed an updated AUMF that is specific to the current conflict; Congress failed to act upon it. The answer is simple: Nathan's orders do not come from Congress; they come from the President, his commander-in-chief. While it is good that the President has acknowledged the need for a new AUMF, the Constitution and the War Powers Resolution place the burden on him to get Congress to agree. By continuing to issue potentially unconstitutional orders to the military in the absence of an AUMF, President Obama is essentially passing the buck to conscientious military service members. Congress must also fulfill its obligations, however. If this suit causes members of Congress to finally take action in providing the military with a clear and updated AUMF for the current conflict, I know Nathan will consider his actions a success.

This is an issue that transcends partisan politics. If the President and Congress allow this situation to continue, they will be setting a very dangerous precedent. A few months back, Donald Trump was asked what he would do if the military refused to follow orders requiring them to torture or target civilians -- orders that are indisputably unlawful. His reply showed a frightening contempt for the responsibilities imposed by the military oath of office: "If I say do it, they're going to do it." This type of thinking -- that our uniformed service members are mindless automatons who are willing to carry out all presidential orders, regardless of legality -- could have devastating consequences when combined with unchecked executive war-making power. We cannot change the dangerous assumptions of presidential candidates. This case, however, challenges Americans to address something that is within our control: we should insist that our representatives stop punting a constitutional dilemma to our military members by putting a decisive halt to America's slide down the slippery slope of unilateral executive war-making.

In bringing this lawsuit, Nathan has knowingly put his Army career in jeopardy. If his fellow citizens back him up, I hope that his sacrifice will help redeem this nation's commitment to the Constitution as the organizing principle of our democracy.