Last week, one of the most significant developments in regards to Turkish-American relations was the meeting of U.S. President Donald Trump with dozens of Republican senators. Reportedly, during the meeting President Trump tried to convince the senators in regards to the potential negative impacts of adopting sanctions against Turkey to the U.S. and its bilateral relations.

Turkey's foreign policy at the moment is full of hot topics, including the S-400 air defense system agreement, the country's removal from the F-35 fighter jet program, potential U.S. sanctions, the Eastern Mediterranean and northern Syria. How those issues are resolved could determine the next four years of Turkish policy.

The S-400 air defense system's delivery to Turkey has sparked debate among Western governments on Ankara's future treatment. The question at hand goes beyond concerns about the fate of Turkey-U.S. relations. This is much bigger than one key NATO ally removing another key ally from the joint F-35 fighter jet program.

The Pentagon removed Turkey from the F-35 fighter jet program, despite U.S. President Donald Trump's earlier comments about Ankara being treated unfairly over its move to purchase the S-400 missile defense system from Russia. That Congress favored Turkey's removal was no secret either. It remains to be seen whether the United States will levy sanctions on Turkey under the Countering America's Adversaries Through Sanctions Act (CAATSA).

Pesident Recep Tayyip Erdoğan's bilateral meeting with U.S. President Donald Trump in Osaka, Japan marked a new chapter in the S-400 dispute. A textbook example of leader-to-leader diplomacy, that meeting paved the way for Trump lending support to the Turkish position on Patriot missiles, the Russian air defense system and the F-35 jet fighter program.

The Justice and Development Party's (AK Party) poll defeat in the Istanbul mayoral election has accelerated political analyses for the coming period. Indeed, the fact that Republican People's Party (CHP) candidate Ekrem İmamoğlu could secure 54 percent of the vote is not just a twist of the alliance system, but also a result achieved by those aspiring to end the 17-year AK party rule through trial and error.

The leader-to-leader diplomacy between the U.S. and Turkey at the G20 summit was crucial in defusing the S-400 dispute and turned it into a potential communication tool for bilateral ties

Since the beginning of Trump's presidency, the two leaders have pretty regularly communicated with each other in face-to-face meetings or through phone calls. This has been an important factor in determining bilateral ties in the last two-and-a-half years.

S-400s are not technical problem but political one, says expert

With the S-400 missile defense system's delivery around the corner, tensions are escalating between Turkey and the United States. The Turks are committed to buying the Russian system despite Washington's threats. The Pentagon's most recent letter to Defense Minister Hulusi Akar, which included a long list of threats, did not change Ankara's mind either.

The United States took its first 'concrete step' to encourage Turkey to rethink its plan to purchase the S-400 missile defense system from Russia. Washington was going to exclude Turkish pilots from the F-35 fighter jet training program, Reuters reported last week.

Turkey has a very busy agenda ahead of itself for the month of June..

Nowadays, it has become commonplace among foreign policy scholars to debate the future of Turkish-American relations.

S-400s are not technical problem but political one, says expert

The crisis in NATO and a complicated U.S. foreign policy are shaping Ankara-Washington relations, making it hard to predict the future

The NATO Council and Mediterranean Dialogue Partners Meeting took place in Ankara earlier this week, at a time when Turkey and the United States are experiencing tensions over the former's plan to purchase the S-400 missile defense system from Russia and disagreements on Turkish drilling in the Eastern Mediterranean.

The Trump administration is using sanctions, mostly economic sanctions, more aggressively compared to earlier administrations. Last summer, Washington imposed national security sanctions on Turkish steel and aluminum due to the detention of pastor Andrew Brunson in Turkey.