How will we be able to trust -- and check -- a president who is indifferent to the truth?

The current season of the television show Homeland may be offering a glimpse of things to come in the real world. It isnt pretty.

The show centers around the Iran Nuclear Deal. In 2015, the United States, five other countries and the European Union reached an agreement with Iran that was designed to avoid military conflict by delaying, if not forever preventing, Iran from developing a nuclear weapon.

The Homeland story line revolves around the question of whether Iran is cheating on the deal. Answering that question requires the characters to separate fact from fiction in a world where truth can get lost in a fog of deception and manipulation perpetrated by parties with ulterior motives.

The stakes are high. Either sanity or war will win the day.

The President Elect about to take office is a smart, moderately dovish woman with a keen nose for political game playing. Shes in no hurry to put the U.S. on a war footing with Iran unless the evidence of Irans cheating on the nuclear deal is unimpeachable.

Smart and savvy as the President Elect may be, she is not entirely immune from the machinations of Dar Adal, a CIA black ops guy. Adal is conspiring with the Israelis in a false-flag operation to manufacture evidence that Iran is cheating on the deal. Hes trying to create a phony narrative that will drive the incoming President to go to war with Iran.

The forever virtuous dynamic duo of CIA operative Saul Berenson and ex-CIA agent Carrie Mathison are digging for the truth. With a back channel to the head of Iranian intelligence, Saul is trying to unravel the web of misdirection spun by Adal. Carrie is helping Saul when she is not otherwise preoccupied with sheltering a former CIA colleague who has been severely impaired by a sarin attack, trying to keep social services from taking her daughter away from her, and generally dealing with her bipolar disorder. Phew! And you think you have problems!

Does any of this sound familiar? Set aside Carries personal struggles. Much of the rest of the Homeland story line hits disturbingly close to home.

The real-life administration of Donald Trump at some point will have to find its own answer to the question of whether Iran is cheating on the nuclear deal. The wrong answer to that question could lead us into a disastrous and unnecessary military adventure.

False narratives have already taken us there twice in recent history.

In 1964, Congress passed the Gulf of Tonkin Resolution, providing legal cover for President Lyndon Johnson to go to war against North Vietnam. The resolution was triggered by two supposed military confrontations with the North Vietnamese in the Gulf of Tonkin. It turned out that one of those incidents never happened, and the other was at best grossly exaggerated, probably deliberately so. Over 50,000 American lives were lost in the Vietnam war, which is widely regarded as the most stunning military defeat in our nations history.

The United States went to war again on a phony premise in 2003 when President Bush invaded Iraq. The primary rationale for the invasion was that Iraq had supposedly amassed a stockpile of weapons of mass destruction that posed an immediate threat to the United States and its allies. To this day, no evidence has been found to support the claim that Iraq had such weapons. Nearly 5,000 American lives were lost. Total deaths are estimated to have been around half a million. The war inflamed the entire Muslim world, and was probably the single most direct cause of the founding and rise of ISIS.

The Vietnam and Iraq wars prove that the risk of being lured by a false narrative into a disastrous war is achingly real. Its history, not fiction. And the stakes are, of course, staggering.

So we have to be able to trust in the truth of any narrative that could lead us into a war. That means we must be able to believe the President of the United States and those around him in times of crisis.

For that reason, and many others, Donald Trumps mendacity about matters big and small cannot be treated as a joke or a distraction. His lack of credibility poses a real danger.

It is not far-fetched to suppose that one day Trump may attempt to justify military action against Iran on the grounds that they are cheating on the nuclear deal. If that happens, will we believe him? Or will we be justly suspicious that the accusation of cheating by Iran has been manufactured by real life zealots like the fictional Dar Adal?

There will be no shortage of Iran-hating Dar Adal wannabes whispering exaggerations and outright lies in Trumps ear. Michael Flynn, Rudy Guiliani, Steve Bannon and Stephen Miller could all step into the Dar Adal role. And these are the guys Trump really listens to.

Nor will there be any difficulty casting the Israeli role. Bibi Netanyahu will play, well, Bibi Netanyahu.

The real question is whether theres anybody who can step into the roles of Saul and Carrie to provide an effective check against Trumps dishonesty.

The most likely candidate for the role is probably the straight-shooting Secretary of Defense, James Mattis. We can count on Mattis to keep Trump honest and guide us toward the truth, cant we?

Maybe not.

Remember the last time we relied on a straight-shooting military man for assurance that we werent being lured by a false narrative into an unnecessary war? In 2003, Secretary of State Colin Powell, a four-star General with an impeccable resume, set the world straight on Iraqs weapons of mass destruction. Straight into war.

Nor can we look to Congressional Republicans to play the role of truth seekers.

The Republicans are enablers of Trumps mendacity, not a check on it. The Republican establishment gets no serious heartburn from Trumps serial lying. They laugh it off and sweep it under a rug of euphemism. Trump isnt a liar, he has a unique personal style of communicating. Hes just expressing frustration. And you cant hold him accountable for lying because hes a neophyte in politics who doesnt have 27 lawyers and staff looking at what he does. Take him seriously, but not literally.

Democrats cant play that role either, because they have no power to change anything. Whatever they say or do is dismissed as sour grapes over a lost election.

So, is there a real Saul or Carrie out there? Will anybody be in our corner, searching for and exposing the truth?

Hopefully, yes. Maybe the press can do it.

Right now, a determined, unafraid, and free press may be all we have to expose Trumps dishonesty and thwart his most ill-conceived adventures. Thats why Trump and his loyalists are working day and night to discredit the press as biased and fake.

The press cant let him do that. They have to call a lie a lie. If Trump lies every day, they have to call him out every day. They cant be worn down. If they have to tell the same story every night, so be it. And they cant be cowed by fear that they will be accused of bias.

Somebody has to expose falsehood and demand allegiance to the facts. Carrie and Saul wont be there to do it for us. They are, after all, just characters on a television show.

This is real.

Philip Rotner is an attorney and an engaged citizen who has spent over 40 years practicing law. His views are his own and do not reflect the views of any organization with which he has been associated. Follow Philip on Twitter at @PhilipRotner.