OK, This Is Not "Sudden".

So, whenever things of this nature are titled like this, one has to ask the question if they even know what are they talking about. 

A fast thaw in relations between the Kremlin and Azerbaijan occurred in March, enabling a strategic link connecting Russia and Iran to keep functioning, despite the ongoing US-Israeli bombing campaign in Iran. Some Western observers believe the route, known as the western branch of the North-South corridor, is being used by Russia to funnel weapons to Iran to keep the war in the Persian Gulf going. Russian-Azerbaijani relations had been tense since Russian air-defense forces accidentally shot down an Azerbaijani civilian airliner in late 2024 and subsequently refused to take responsibility for the tragedy. Until recently, the two countries had continued to trade diplomatic barbs. But the tone in bilateral relations suddenly changed following a March 2 meeting in Baku between Russian Deputy Prime Minister Alexei Overchuck and Azerbaijani leader Ilham Aliyev, discussions that took place just days after the start of the US-Israeli aerial campaign in Iran. A statement issued by Aliyev’s office indicated that the meeting managed to settle the issue of the accidental shootdown. It also noted that both sides “reaffirmed their commitment to continuing efforts to advance the International North–South Transport Corridor.”

OK, let me explain: 

1. Look at the map:

Russia and Azerbaijan have a substantial land border and share Caspian Sea. To the South Iran and Azerbaijan share even longer border. Moreover, Azerbaijan and Turkiye share only a teeny-weeny land common segment through Azerbaijan's exclave Nakhchivan which is separated from mainland by ... Armenia. Hence the issue of Zangezur Corridor. 

2. Turkiye, for all her potential and development is still not in premier league. In the same time, Russia is a global superpower and she also has a very large Azerbaijani community which is one of the major pillars of ... Azerbaijan's economy. 

3. Now, the issue of Iran, which already emerged, despite the damage, as a LEADER of Ummah demonstrating courage, military sophistication and immense influence on global affairs by controlling Strait of Hormuz and parading the US and Israel as military paper tigers in head-to-head clash--this is serious. 

4. And then, both Azeris and Iranians are Shiites. That matters hugely. Erdogan talks a lot, Iran does and already achieved a strategic victory. 

That's the balance sheet for Ilham Aliev's consideration. Apart from many other items. So, whose side will Azerbaijan take? It is sandwiched between global superpower and regional superpower, both of who are de facto and de jure--allies. These allies also need land corridor to each-other and Azerbaijan is placed exactly in the middle of this corridor. Now, especially against the background of the latest events, Aliev must ask himself  a number of questions:

a) How safe are Aliev clan's assets in UK and other banks, especially with the West being bankrupt and facing economic (militarily it already happened) destruction?

b) Does Azerbaijan want to be associated with a critical Eurasian military-economic monster which is RIC (Russia-Iran-China) and profit from it--the rewards already now seem to be astronomical--or will it continue to look towards imploding West? 

c) In the end, SMO is a message to all Russia's limitrophes who decided to bet their houses on the West's promises. And how's that relations between Azerbaijan and Israel are going, with Israel and its pathetic military being beaten in the bloody pulp. Evidently somebody in Azeri military, who probably graduated from the campus of my former naval academy, which is today serves as Geidar Aliev Military Institute, failed in real military analysis of Israel's REAL power.  

I would say, Aliev simply has no choice, especially considering an uneasy economic situation in Azerbaijan. Moreover--never forget "the street" be it Arab street, Azeri street et al--people on the street see what is going on and they take note. So ... it all comes naturally, if you know what I mean.