Three weeks ago, the Israeli defense minister Benny Gantz visited Ankara, where he met with his Turkish counterpart as well as with President Recep Tayyip Erdogan, in what seemed a further step toward reconciliation between the two countries. Yet Turkey still refuses to accede to Jerusalem’s requests that it expel Hamas from its territory. Ankara, now reeling from a terrorist attack, has been in a difficult position both economically and diplomatically for some time, and it is easy to see how it might benefit from mending fences with one of the strongest powers in the region. But what, asks Eran Lerman, is in it for Israel?

Clearly, at the core of the two countries’ mutual concern at this point is the growing challenge posed by reckless Iranian conduct. In recent months, this has become a highly specific threat to basic Turkish interests, creating common ground with Israel. The immediate trigger for this new impetus for cooperation was the effort by Iranian agents to use Turkish soil for attacks on Israeli citizens—tourists or businesspeople visiting Istanbul—as an act of revenge against Israel’s alleged complicity in the killing of Islamic Revolutionary Guard Corps operatives on Iranian soil.

The Iranian challenge to both countries is not, however, confined to such terror tactics. Israel and Turkey (and Pakistan as well) share an ally currently under active Iranian threat—Azerbaijan. It is close to Turkey in language, culture, and heritage as well in strategic terms. At the same time, since its independence in 1992, it has been a friend (and energy supplier) of Israel and a significant client of Israel’s defense industries. Following the Azeri success in the Nagorno-Karabakh War of autumn 2020, both Turkish and Israeli flags could be seen in the streets of Baku.

Within the last few months, Iranian threats against Azerbaijan have become more intense, backed by force concentrations and military exercises at the border.

Noah Rothman provides a worthwhile reminder of why a nuclear Iran is a threat not just to Israel, but to the United States:

For one, Iran is the foremost state sponsor of terrorism on earth. It exports terrorists and arms throughout the region and beyond, and there are no guarantees that it won’t play a similarly reckless game with nuclear material. At minimum, the terrorist elements in Iran’s orbit would be emboldened by Iran’s new nuclear might. Their numbers would surely grow, as would their willingness to court risk.

Iran maintains the largest arsenal of ballistic missiles in the region. It can certainly deliver a warhead to targets inside the Middle East, and it’s fast-tracking the development of space-launch vehicles that can threaten the U.S. mainland. Even if Tehran were a rational actor that could be reliably deterred, an acknowledged Iranian bomb would kick-start a race toward nuclear proliferation in the region. The Saudis, the Turks, the Egyptians, and others would probably be compelled to seek their own nuclear deterrents, leading to an infinitely more complex security environment.

In the meantime, Iran would be able to blackmail the West, allowing it occasionally to choke off the trade and energy exports that transit the Persian Gulf and to engage in far more reckless acts of international terrorism.

As for the possible consequences, Rothman observes:

Iranian retaliation might be measured with the understanding that if it’s not properly calibrated, the U.S. and Israel could begin taking out Iranian command-and-control targets next. If the symbols of the regime begin crumbling, the oppressed Iranian people might find the courage to finish the job. If there’s anything the mullahs fear more than the U.S. military, it’s their own citizens.