Is the PYD a threat to Turkey?

The USA’s president with his hair dyed tawny orange, Donald Trump, has announced that he will give heavy weapons to the PYD’s armed wing, the YPG, in the war against ISIL in Syria.

Precisely or almost precisely on the eve of Tayyip Erdoğan’s 16 May visit to the USA for talks with the president.
This is quite obviously, putting it mildly, a ‘cold shower’ for the AKP regime, or, to put it less mildly, ‘an unexpected blow.’
In fact, a stream of comments has emanated from the government front.
A pronouncement came from soon-not-to-be Prime-Minister Binali Yıldırım:
‘The USA must make a choice. It is impossible for us to accept procedures that amount to direct or indirect aid for the PKK.’
Then Foreign Minister Mevlüt Çavuşoğlu chimed in:
‘Every weapon that passes to the YPG is a threat for Turkey.’
The reply to these reactions came from Secretary of Defense Jim Mattis on behalf of the US administration:
‘We are keenly aware of the security concerns of our coalition partner Turkey. We want to reassure the people and government of Turkey that the U.S. is committed to preventing additional security risks and protecting our NATO ally.’
I do not know how those versed in diplomatic language will interpret and assess Jim Mattis’ reply. To me it came a bit like the consolation from the man who assists a boy during his circumcision, ‘Don’t be afraid, it won’t hurt. Just a bit at the end.’
But, do not pay too much attention to what I say: that language is not a language I know. Perhaps I have misunderstood.
It is not my business, in any case, to write about the cold winds blowing between Erdoğan and his team and the Trump administration, whose election came as the source of hope to the AKP regime and joy to the AKP media.
***
But, I deem it worthwhile to inquire whether the PYD and its armed wing, the YPG, indeed pose a threat to Turkey.
The PYD is the Syrian Kurd’s political organ. It is a party. Its Kurdish name is Partiya Yekîtiya Demokrat, meaning ‘Democratic Union Party’. It was formed in 2003. It has adopted the political line set by Öcalan. It has strong relations with the PKK.
The YPG, for its part, is the PYD’s armed wing. Its Kurdish name is Yekineyen Parastina Gel, meaning ‘People's Protection Units’.
Öcalan has been in a state of complete isolation for a long time. I do not know if he has changed his opinions in the lengthy intervening time. What I know is that he rejects the establishing of a Kurdish nation state. Even if it comes across as utopian to some, he persistently advises the sections of the Kurdish political movement over which he holds sway to steer clear of the ideal of establishing a nation state. He advocates, not Kurds breaking away from Turkey, Iraq, Syria and Iran, where they live, and establishing an independent state on that territory, but those countries retaining their national borders but, through weakening these, building up the strongest possible economic, political and cultural ties.
For some people, these are preliminary steps, preparations, in the direction of a prospective Kurdish nation state.
But this is to read meaning into it. However, the HDP in Turkey and the PYD in Syria have on countless occasions stated their commitment to remaining within this political sphere. Selahattin Demirtaş has underlined this at every opportunity. There are comments in the same vein from Salih Müslim on behalf of the PYD.
No comment, or even rhetoric, has been heard in which either political party has deviated from this orientation.
So, under such circumstances, why should the rising to prominence of the PYD in the Kurdish regions that stretch along Turkey’s border with Syria and its reaching an agreement based on autonomy with the Syrian regime pose a threat to Turkey?
Quite the reverse, will it not prevent the porous border from becoming the wayside inn of ISIL and similar pseudo-religious terrorist organisations?
In Syria today, it is the Kurds, the YPG, who are waging the most serious fight against terror-wreaking Islamist organisations, large and small, from ISIL to Al-Nusra. Until the contrary is proven to be true, if declaring the PYD to be a threat is not giving the green light to Islamist terrorists, what is it?