DW: Mr. Fathollah-Nejad, Iran's medium-range missile test was met with warnings from President Donald Trump's national security adviser, Michael Flynn, and Secretary of Defense James Mattis. How serious are these warnings?

AFN: It's too early for me to judge. Even before Trump's inauguration, we knew of General Michael Flynn's hard stance on Iran. For him, regime change is the only solution to the problem.

James Mattis is closer to the international consensus that supports the nuclear deal. However, it is important to bear in mind that the center of power in Washington is not at the State or Defense Departments, but at the White House, where the president has surrounded himself with hardliners. Of course, it's hard to argue that Iran's missle test in TrumP's second week in office constitutes a policy of detente.

The warning also comes during an extremely controversial start for Trump, both on national and international levels. It could be understood as preparation for a war-footing against Iran to distract from a future domestic crisis. That would be an undoubtedly risky maneuver that could lead to a wider war with unimaginable consequences.

Contrary to Washington, Iran claims the test did not violate UN Resolutions. How do you see it?

That refers to UN Resolution 2231 from July, 2015, which "welcomes" the so-called Iran nuclear deal between six  major powers and Tehran. 

Iran was called upon, if not legally obligated, "not to undertake any activity related to ballistic missiles designed to be capable of delivering nuclear weapons, including launches using such ballistic missile technology."

Opinions differ as to whether the missile test constitutes nuclear capability, but Iran rejects the claim. In any case, the missile tests are not a factual violation of the deal.

Trump's team stated it will consider several options in response to the test, including military ones. Which options do you see as most realistic?

In addition to imposing additional, unilateral US sanctions, smaller actions in the Persian Gulf against Iranian speed boats and naval vessels are within the realm of possibility.

In light of a harder American line, how likely do you see the possibility of the US leaving the nuclear agreement? Would it be so easy to do under international law?

A unilateral withdrawal is certainly possible, but the smarter diplomacy would be to pin it on Iran. Washington's withdrawal is anyway possible because the Iran nuclear deal isn't binding under international law. Ratification by the US Senate or similar Congressional approval would be necessary, and neither is likely.

How much influence do European countries, especially Germany, have in de-escalating the situation?

The three EU countries that are part of the deal, ideally with China and Russia, could make a clear case to the US that the deal must be guaranteed to keep Iran from becoming a nuclear power within the foreseeable future. It would also be advisable to point out the position of most of the states that are part of the Gulf Cooperation Council to keep the deal in place, given the aforementioned security dimensions and despite their deep concern for Tehran's overall regional policy.

Ali Fathollah-Nejad is a Berlin-based political scientist. He is currently an associate fellow at the German Council on Foreign Relation's Middle East and North Africa Program as well as an associate at Harvard Kennedy School's Iran Project.