In Iraq, Kurdish militiamen fighting the group that calls itself the Islamic State are key American allies.
In Syria, some Kurdish fighters battling the very same Islamic State are considered part of a terrorist group, according to the U.S. government.
What gives?
In both Iraq and Syria, the Kurds are a long-repressed minority who are fighting back against the threat posed by the Islamic State. In the northern parts of both countries, Islamic State advances have driven large numbers of Kurds from their homes. In the latest upheaval, an Islamic State offensive has driven more than 100,000 Kurds from northern Syria into Turkey in just a matter of days.
With the U.S. military now bombing in Syria and in urgent need of allies on the ground, why does the U.S. have such of dim view of Kurdish fighters in Syria when it is counting so heavily on the Kurdish fighters in Iraq?
The U.S. also says it's going to train "moderate" Syrian rebels, a process that could take a year to generate some 5,000 fighters. Yet the U.S. has given no indication so far that it's prepared to work with the Kurdish militias in Syria that are already clashing with the Islamic State.
Well, it's the Middle East, so it's complicated. And it involves the Kurds, so it's beyond complicated.
There is no short answer. Here's a short-ish answer:
In Iraq, Saddam Hussein persecuted the Kurds throughout his brutal rule, using chemical weapons to wipe out as many as 5,000 Kurds in the village in Halabja in 1988. The Kurds, therefore, staunchly supported the U.S. wars against Saddam and developed a close relationship with the U.S. military, which helped train the Kurdish peshmerga fighters.
The Kurds, who formally achieved semi-autonomy in the northern Iraq nearly a decade ago, have their share of problems, including recurring internal divisions. Still, their enclave has been the most peaceful and prosperous part of Iraq in recent years.
Kurdish fighters have resisted the advances of the Islamic State, and when the U.S. began bombing the extremist group, Kurdish forces swiftly moved into areas vacated by the group. The U.S. and the Kurds would like to replicate this model throughout northern Iraq.
Meanwhile, there are plenty of parallels in Syria, where the Kurds have been repressed for decades by the current president, Bashar Assad, and his father, the late Hafez Assad.
There's one key difference. The Kurdish militia in Syria, known as the YPG, is closely aligned with a militant Kurdish group in Turkey, the PKK, that has fought for Kurdish self-rule since the 1980s.
In that long battle, Turkey declared both PKK and YPG terrorist groups.
The U.S., as a fellow NATO member, concurred with Turkey's assessment and put the Turkish PKK on the U.S. terrorist list back in 1997. The U.S. did not add Syria's YPG, but has acknowledged the close relationship and has ostracized the Syrian Kurdish militants as well.
Yet this old policy is being challenged by the new realities.
The Turkish and Syrian Kurdish militias have both battled the Islamic State in ways that have directly helped to the U.S. effort.
"Syrian and Turkish Kurdish fighters are gaining influence and a stronger foothold. America can no longer ignore them," analyst Aliza Marcus, who has studied the Kurds for years, wrote recently. "The Kurdish groups from Syria and Turkey reject radical Islamism. They are secular nationalists and natural American allies."
The strongest example was in August, when the U.S. carried out airstrikes against the Islamic State to assist the Yazidis, a religious minority that had thousands of members trapped in desperate conditions on the barren Mount Sinjar in northern Iraq.
The quickest escape route for the Yazidis was to neighboring Syria, where the Syrian Kurds of the YPG helped protect them from the Islamic State and guided them to safety.
As in Iraq, the Kurds in northern Syria have carved out a semi-independent enclave and could potentially be part of the ground force the U.S. is looking for to beat back the Islamic State.
But that would require a change to the long-standing U.S. policy toward the Kurds that has tended to follow this strange rule:
If the U.S. is friendly toward a government (think Turkey), then it doesn't support that country's Kurdish nationalists. If the U.S. despises a government (think Saddam's Iraq), then it sympathizes with that country's Kurds. One exception was Syria, where the U.S. didn't like the government or the Kurds.
But the upheavals in the Middle East have meant discarding many old rules.
Last year, Turkey reached a ceasefire with the PKK. In addition, Turkey is coming to view the Kurdish areas in neighboring countries less as a threat and more as a buffer from the chaos in Syria and Iraq. Turkey is now, for example, trading extensively with the Kurds of northern Iraq.
U.S. calculations are changing as well, as the Americans urgently search for allies in Syria. The Kurdish YPG militia, stiffened by several years of fighting in Syria, said Monday it had halted the latest advance by the Islamic State. The Turkish PKK forces were also reported to be involved in the clashes.
For generations, the Kurds have felt ignored by the West and repressed by assorted rulers in the Middle East. Now they seemed destined to play a larger role.
"If Mr. Obama really wants to ensure no boots on the ground,: wrote Marcus, the expert on Kurds, "he will have to rethink America's policy toward Kurdish nationalism, and recognize the Kurds, and not only Iraqi ones, are his main ally against (the Islamic State)."
Greg Myre is the international editor of NPR.org. Follow him @gregmyre1
Copyright 2014 NPR. To see more, visit http://www.npr.org/.