There are rich people everyone knows about, and rich people who deliberately stay in the shadows - and it is usually the latter who hold the most power. Sheikh Mohamed bin Zayed Al Nahyan, ruler of Abu Dhabi and president of the United Arab Emirates, belongs to the second group. According to a Bloomberg analysis, his wealth is estimated at an astonishing 335 billion dollars - a sum that places him among the richest and most powerful people on the planet.

What makes him more interesting than an ordinary billionaire is the way he handles that money. Behind him stands a family investment office, AC Limited, which pours capital into giants like Amazon, Microsoft and Nvidia. In other words, some of the companies that shape our everyday lives - from online shopping to artificial intelligence - have Abu Dhabi capital behind them too. Power that does not show up on the front pages, but is everywhere.

And here comes the Balkan thread. According to the same analysis, the sheikh is a close friend of Serbian president Aleksandar Vucic, with repeated visits to Belgrade and talks about economic cooperation, investment, air traffic, tourism, infrastructure and energy. Gulf capital stopped being a distant story for the region long ago - it is already here, in projects some of which are boasted about loudly and some quietly.

It is worth asking what a friendship like this means for a small region. When a man worth 335 billion invests in your country, he rarely does it out of affection - capital wants a return, influence or a strategic position. That is not bad in itself; but the citizen has the right to know what is given in exchange for those investments. Because Gulf money comes with conditions, even when the conditions are not written out at a press conference.