Officials in Turkey’s ruling party threatened this week to invade Greece to take control of disputed islands in the Aegean Sea.

As Hurriyet Daily News tells it, the situation began shifting from long-simmering back-burner grievances to a bubbling pot of war threats in 2016, when Ozturk Yilmaz assumed the deputy chairmanship of Turkey’s main opposition party, the Republican People’s Party (CHP).

Hurriyet describes Yilmaz as a fire-breathing populist-nationalist who “was not exactly among the brightest” of Turkish politicians. He went looking for a soft spot in Erdogan’s party he could hit with a barrage of populist rhetoric and decided to needle the Justice and Development Party (AKP) for its soft stance on reclaiming the Aegean islands from Greece.

Turkey controlled the islands until losing them to Italy in the 1923 Treaty of Lausanne, which formally concluded World War 1. The war saw the death of several empires, prominently including the Ottoman Empire of Turkey. Turkey lost its Aegean possessions but got to keep Turkish Kurdistan. Current President Recep Tayyip Erdogan and his AKP party do not like the first half of that deal, and the Kurdish separatists of the PKK party do not like the other.

The islands passed from Italy to Greece, so getting them back would involve either winning legal disputes with the Greeks or attacking them. The legal disputes have been grinding along since 1996, so the Turks are growing impatient.

The inconvenient historical fact that the CHP was the ruling party of Turkey in 1923 and signed the Treaty of Lausanne gave Yilmaz little pause.

The official Turkish government line on the Aegean dispute is that Erdogan and Greek Prime Minister Alexis Tsipras have spoken by telephone and arranged a meeting between their respective chiefs of staff to reduce tensions. It would also reduce tensions quite a bit if both AKP and CHP leaders would stop talking about invading Greece to take the islands by force.

Erdogan is one of those leaders, as the Gatestone Institute points out. Flush with war fever after his invasion of Syria to fight the Kurds of Afrin, Syria, Erdogan declared in a speech last week, “Whatever Afrin is to us, our rights in the Aegean and Cyprus are the same.”

Erdogan portrays the invasion of Afrin as a patriotic crusade that cannot be questioned by any true son or daughter of Turkey without facing charges of treason.

“Just as we disrupt the plots through Operation Euphrates Shield and Operation Olive Branch, and soon in Manbij and other regions, we can and we will disrupt the plots of those who engage in miscalculations on our southern border,” Erdogan said. “Our warships and air forces are keeping an eye on the area closely to intervene in every way when required.”

Operation Olive Branch is the name sarcastically given to Turkey’s invasion of Syria, which Erdogan portrays as a quest to achieve peace by killing every Kurdish “terrorist” in the region. Manbij is the next city in Syria he has been threatening to attack. There are hundreds of American troops stationed in Manbij.

Erdogan then extolled the glories of the Ottoman Empire and threw in a little Islamist rhetoric for good measure:

We say at every opportunity we have that Syria, Iraq and other places in the geography in our hearts are no different from our own homeland. We are struggling so that a foreign flag will not be waved anywhere where adhan is recited.

Adhan is the Muslim call to prayer. Erdogan was, in essence, calling for a jihad to reclaim every bit of land Turkey has ever considered part of its “homeland” so he can build a new caliphate. He wrapped up his remarks by warning that what he has done in Syria pales in comparison to the “even greater attempts and attacks in the coming days, Allah willing.”

The Gatestone Institute notes that Turkey’s government religious ministry, the Diyanet, has explicitly referred to the Afrin operation as a “jihad.” Turkey’s previous jihads to seize or ethnically cleanse “homeland” turf have been insanely bloody affairs, including the Armenian genocide Turkey denies to this very day.

Erdogan is hardly the only Turkish leader talking this way about Greece. The current leader of the CHP, Kemal Kilicdaroglu, continued the effort to outbid Erdogan on Aegean belligerence by explicitly promising to “invade and take over 18 Greek islands in the Aegean Sea” if he prevails in the 2019 elections.

Kilicardoglu portrayed the islands as illegally occupied by Greece, insisted there is no documentation proving Greek ownership, and compared reclaiming them to Turkey’s 2015 military operation in Syria to protect the tomb of Suleyman Shah, the revered grandfather of the first sultan of the Ottoman Empire. In other words, the CHP leader was saying the Greeks squatting on those Aegean islands are comparable to the Islamic State, which was threatening to defile the tomb in Syria.

The Gatestone Institute’s roundup includes Meral Aksener, the leader of the newly-minted IYI Party, also known as the “Good Party,” which was established to offer a positive alternative to Erdogan’s authoritarian rule. Aksener is a charismatic female politician hailed as a serious threat to Erdogan in the next election, but she thinks the Aegean islands are “occupied homeland” that should be reclaimed by force, too. Aksener portrays such an invasion as a regrettable necessity rather than a thrashing those lousy Greek occupiers have coming to them.

Turkey’s pro-Erdogan Yeni Safak newspaper quoted the president and his Chief of Staff Hulusi Akar to the effect that Turkey is perfectly capable of fighting in Syria and Greece at the same time, and also quoted an unnamed high-level Turkish military officer who says plans for an invasion have been on the drawing board ever since Erdogan survived the July 2016 coup attempt against him. That would be the same Hulusi Akar that Erdogan will send to speak with Greece about the fate of the islands.

At the very least, it seems that few Turkish politicians want to risk being seen as soft on the Aegean, which is a disturbing prospect in a nation with Turkey’s current psychology and military capabilities. As Yeni Safak implies, it might also be an effort to rattle the Tsipras government in Greece, bullying them into making concessions in negotiations over the fate of the islands.

The war talk might also be an expression of general Turkish unhappiness with Greece over issues such as Athens’ refusal to extradite Turkish soldiers accused of participating in the coup attempt against Erdogan. According to the Greek government, the number of Turkish nationals seeking asylum in Greece has increased tenfold since the coup, leaving Greece second only to Germany as the destination of choice for Turks fleeing Erdogan’s wrath.

Greece has indicated it will fight if necessary.

“The Greek armed forces are ready to answer any provocation. We are ready because that is how we defend peace,” declared Greek Defense Minister Panos Kammenos last March, speaking at a military parade on the 196th anniversary of Greece’s war for independence from the Ottoman Empire.

The larger problem is that the international community might feel obliged intervene against Turkish aggression, which could include NATO, which happens to count both Greece and Turkey as members. That means Turkey could potentially become embroiled in two conflicts that could blow NATO apart, one in Syria against U.S. troops, and the other in the Aegean against Greece.