"For the sake of stability, it is important that [the Americans] do accept the reality of Rojava (the way Kurds call Syrian Kurdistan). It is an oasis within a morass of instability," Demirtas told WorldViews at a hotel in Washington. "Only by taking it as your starting point can you get a solution and stability in Syria."
Demirtas, a charismatic politician who heads the Peoples' Democratic Party (HDP), believes that a PYD-led autonomous region would embody the politics needed to fix the rest of war-torn Syria.
"They are building a pluralist democracy over there," he said. "They are preventing the partition of Syria and they're preventing a new dictatorship from emerging. It's also a blow to the ideology of IS, because they believe in a secular system."
This position is anathema to Turkey's ruling government and its president, Recep Tayyip Erdogan. During a visit to Washington at the end of March, Erdogan urged the West to see the violence of Kurdish separatist groups in Turkey in the same light as the terrorism of the Islamic State.
The violence between Turkey and the Kurdistan Workers’ Party (PKK) has been a disaster for Demirtas and his party, which sees itself caught between the strong Turkish nationalism of the state and the excesses of its erstwhile brothers in the mountains.
"We are not the legal arm of the PKK, we are an entirely independent political party. But there is certainly a lot of overlap between the people who vote for us and the people who support the PKK," Demirtas said. He described the HDP, which combines a strain of Kurdish nationalism with broader leftist, pluralist politics, as an "alternative to violence" in the country.
"The Kurds are a reality, and in every country in the Middle East, in Iraq, Turkey, Syria, they are on the front lines for the struggle of democracy," Demirtas said. But he argued that Erdogan, instead of seeing Kurdish aspirations as an opportunity, viewed them as a threat.
"There's a fundamental ideological conflict between the Kurds and Erdogan, who has a Turkish Islamist ideology," Demirtas said. "He wants Muslim Kurds under his hegemony. But Kurds won't accept that."
In parliamentary elections in November, many conservative religious Kurds did choose to vote for Erdogan's Justice and Development Party, rather than the HDP. Intra-Kurdish rivalries between various factions shape the ethnic group's political status quo across borders in Turkey, Syria and Iraq.
In Washington, Demirtas said U.S. officials need "to play a much more encouraging role" not only to help establish better relations between Ankara and the Syrian Kurds, but also to help push for peace within Turkey.
"Turkey is sliding toward instability step-by-step and not enough is being done to stop that," Demirtas said.