David A. Andelman, member of the board of contributors of USA Today, is the author of "A Shattered Peace: Versailles 1919 and the Price We Pay Today." He formerly served as a foreign correspondent for The New York Times and CBS News. Follow him on Twitter @DavidAndelman. This opinions in this article belong to the author.

(CNN) At first glance, it appears that there are only two clear paths that the US can take when dealing with the Middle East: the Sunni path of Saudi Arabia and the bulk of its Gulf allies, on the one hand; or the Shiite path represented by Iran.

There is the path of dictators -- like Egypt's autocratic Abdel Fattah el-Sisi, the blinkered and aging royal family of Saudi Arabia, and the corrupt and helpless rulers of Iraq -- all Sunnis.

By contrast, there is the young and desperately eager majority of Iranians, all Shiites, seeking to drag their nation out from under the yoke of a medieval clerical oppression.

The Trump administration, seduced by an effusive Saudi welcome -- in sharp contrast to anything provided his predecessor, Barack Obama -- may be taking the wrong road.

The correct, if difficult, third path for America is to straddle between Sunni and Shiite. But going on the evidence of Trump's first overseas trip to Saudi Arabia and Israel -- both firm enemies of Iran and critical of the Obama administration's perceived warmth towards Iran -- this is a path that the President seems determined to ignore.

Such a path is especially important since the landslide victory Friday of Iran's President Hassan Rouhani in his bid for a second term, and the suggestion that Iran's Shiite leadership may be preparing for a new and more enlightened future for its people.

Of course, while that new road can be paved with good intentions, we know where such paths can lead. Still, it is of vital importance that we give these youths a chance to explore it.

Rouhani's 57% victory over his opponents in Friday's election was clearly a clarion call from the nation's increasingly young, urbanized and westernized middle class for a recognition of their aspirations for a dramatic break with the past. Yet the Trump administration seems hell bent on ignoring all such cries.

What incentive is there for Iran to move toward peace, toward the West and toward the US if we become known not as peacemakers but simply arms merchants to Iran's sworn Sunni enemies in Saudi Arabia?

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It was decidedly not a gesture to the reality that this is precisely what these very Iranian people voted for two days earlier.

Yet under the leadership of the blinkered Trump administration and the Sunni dictators to which it has hitched America's wagons, these forces of potential progress in Iran are being given few choices but to look elsewhere for weapons to defend their Shiite faith and their nation against the weapons being stockpiled by their Sunni enemies.

And there will be no shortages of potential arms merchants to Iran. We have only to look to the list of nations congratulating Rouhani on his remarkable victory . Russian President Vladimir Putin, China's Xi Jinping, even the foreign policy chief of the European Union, Frederica Mogherini, weighed in with warm wishes.

But there is more to the new era that may mark the path of Iran. If, as now appears increasingly likely following the weekend's events in Riyadh, the Sunni-Shiite divide continues to widen, it will have unfortunate consequences for the war on terrorism that President Trump seems so intent to pursue in short-sighted alliance with questionable partners.

For while the battle against ISIS is quite clearly a battle -- as President Trump has expressed it -- between good and evil, it is also a conflict that has gone on for centuries between Sunni and Shiite.

Today, it is ISIS whose leaders profess the Sunni religion , as did al Qaeda before them and a host of other rebel forces and tribes into a dark and terrifying past. Few forces have been effectively arrayed against them. Kurdish troops have held their own in a succession of bitter and deadly battles.

It is Iran, and its powerful Shiite forces, that -- if unleashed en masse against ISIS in their strongholds in Syria and what remains of their holdings in Iraq -- could end the reign of terror of ISIS in the blink of an eye

Trump and his advisers seem to be acting on the ancient pronouncement that the enemy of my enemy is my friend. They simply have been unable or unwilling to identify who could be our real and true enemies, and who our long-term friends.

Iran, apparently, no matter how vocally its people scream for change, will continue to find only deaf ears from Washington to Riyadh.