Bilateral ties between Turkey and the U.S. have their own strong and irrevocable roots in the trajectory of diplomacy irrespective of governments and ruling parties. Nearly one-and-a-half decades of Justice and Development Party (AK Party) rule has witnessed historical moments; ups, downs, collaboration and crises. Historically, neither embargoes nor pressure could swerve Turkey from what it knew was right on national security issues of greatest importance, such as Cyprus.March 2003 was the turning point when Turkish-U.S. relations entered a particularly fractious phase because of Parliament's refusal to use its territory for the invasion of Iraq.Since then, more issues have crept up to poison bilateral ties, especially concerning developments on Iran, Syria, Egypt and again Iraq. The U.S. severely criticized Turkey for maintaining its belief that diplomatic avenues should be exploited to resolve the crisis over Iran's nuclear program. Soon afterward, it was the U.S. itself that resolved the Iran crisis through diplomatic means, as Ankara had argued from the beginning. Ankara kept its opinions on the discrepancy of U.S. attitudes to itself and moved on.Ankara's proposal for the international community to establish ties with the Bashar Assad regime to maintain dialogue for progress before the current crisis fell on deaf ears and was once again criticized by Washington. The U.S. was of the opinion that maintaining any sort of ties with Assad was wrong and the regime should be toppled at once.The escalation of the violence in Syria moved Ankara toward the opinion that Assad had to go. However, this time it was the U.S. that was cool toward any attempt to remove Assad, maintaining that what was happening in Syria was not a priority. This sudden zigzag was also something that Ankara noted, but decided to keep its opinions to itself.While Turkey saw the ouster of Egyptian President Mohammed Morsi as a coup, the U.S. chose to describe it as the restoration of democracy. Such differences of opinion caused tolerable ups and downs in bilateral ties. These differences were never perceived as threats to Turkey's national security.However, the current tension between Ankara and Washington comes from their positions at opposite poles of an issue that threatens Turkey's national security. Previous disagreements had a cost to both sides but never before had such disputes clearly threatened the national security of either country.The Democratic Union Party (PYD) and its armed People's Protection Units (YPG), which pose a clear and present danger to Turkey's security, are openly supported by the U.S. Such a stance can never be pushed under the rug. This is not a tolerable disagreement among friends. The U.S. administration is recklessly and irresponsibly trying to fool the entire world by claiming that there are no links between the terrorist PKK and the PYD. By sacrificing the security of its ally to its own narrow interests, it shows to all how unreliable it is. A moderately resourceful high school student anywhere in the world could surmise that the PKK and PYD are one and the same and attempts to set them apart fool no one. Arguments extended by the U.S., which has the most developed intelligence system in the world, convince no one, and Washington's attitude is having a discernibly adverse effect on bilateral ties with Turkey. The U.S. seems content to follow this route in the belief that when the time comes the two countries can simply kiss and make up. If the U.S. truly holds this erroneous view, it should take a glimpse of the bodies of dead civilians and soldiers falling victim to the PKK's daily attacks and the growing anger among the Turkish public about U.S. policies. There will be no going back for the loss of trust among the Turkish people and their leaders, and the regional cost to the U.S. for its decrepit policies will be considerable.U.S. President Barack Obama's irresponsible policies on the PKK and PYD are not estranging only President Recep Tayyip Erdoğan's administration, but also the entire country. If Obama defines pushing the Turkish government away and losing the favorable Turkish public opinion as an affordable price to pay his foreign policy vision, he will be recorded in history as a failed president who oversaw the collapse of ties with Turkey to the detriment of U.S. national interests. Is Turkey alone in regarding Obama's policies as seriously detrimental to bilateral ties? Just ask U.S. allies in the region what they think about Obama's policies in the Middle East.