Maybe it was tit for tat.

Maybe it was just a coincidence.

But when a Russian air strike on Syria accidentally killed three Turkish soldiers and wounded 11 others last month — 13 months after Ankara unintentionally downed a Russian warplane in roughly the same area — it definitely threw a wrench into the budding bromance between Vladimir Putin and Recep Tayyip Erdoğan.

And it isn’t like the on-again-off-again courtship between the two was all that rock-solid to begin with.

Putin, of course, extended his condolences for this misfortunate Feb. 9 incidence at al-Bab, just as Erdoğan did (albeit belatedly) for the 2015 episode.

But we are talking about two ego-heavy megalomaniacs, here, and neither of them is very inclined to let bygones be bygones.

It is worth noting that while Putin issued words of contrition to Erdoğan regarding the al-Bab debacle, he never quite took full blame for the incident, suggesting that the strike was based on erroneous military intelligence provided by Ankara and adding that the Turkish soldiers were partly responsible for their own friendly-fire causalities because they were carelessly operating in the wrong place at the wrong time.

So, in spite of a recent surge in bilateral economic and political ties — strongly boosted by Moscow’s unflinching support of Erdoğan after the failed July 2016 coup attempt against his government in Ankara — the loosely cloaked marriage of convenience between the two regional powers may soon be headed for divorce court.

In recent months, Moscow and Ankara have joined forces in their efforts to quell the inexorable sectarian and factional violence that has turned Syria into a cauldron of political anarchy.

But while Erdoğan, spurred on by his own self-interest, has tentatively acquiesced to Putin’s more authoritative position on the Syrian front, the former footballer-cum-politician is still playing defense with the Kremlin over how Putin plans to deal with the embattled country’s malcontent Kurds, who make up about 10 percent of its 18-million-strong population and who Erdoğan believes are helping the separatist terrorist group Kurdistan Workers’ Party (PKK) inside his own territory.

Moscow’s recent proposal to establish a secular constitution for a federated Syria (which would essentially constitute the establishment of a semi-autonomous Kurdish territory) has not sat well with Ankara (nor, for that matter, with Syrian President Bashir al-Assad).

For now, both Ankara and Moscow are trying to downplay the mounting tensions that have threatened to dissolve their consortium, focusing their joint efforts instead on destroying the Islamic State (I.S.), neutralizing Syria’s ménage of insurgent militants and reestablishing a semblance of political stability in a country that has been torn by more than six years of internal strife.

The relationship between Putin and Erdoğan is certainly one of mutual geopolitical advantage, and that opportunism will continue to be defined by current global issues.

But at the heart of the Putin-Erdoğan alliance is the fact that both men are hell-bent on asserting their own political power in a region that is as volatile as a powder keg and as unstable as francium.

It was that similarity of purpose and converging interests that was behind last year’s diplomatic rapprochement between Moscow and Ankara, and it is that same shared ambition that will ultimately lead to the downfall of the Russian-Turkish love affair.

Thérèse Margolis can be reached at [email protected]