Bahrain has arrested 41 people linked to Iran's Revolutionary Guard. At the same time, the US has rolled out fresh sanctions on four firms - three of them based in China - accusing them of "providing satellite imagery that enables Iranian attacks on American forces." The same day the Treasury sanctioned another ten individuals and companies for helping Iran procure weapons and materials for ballistic missiles and drones.

The whole operation lands at a specific turning point. The US Navy is holding a blockade over Iranian ports, and CIA analysts estimate Iran can outlast the blockade at least through the end of summer. Alternative routes are opening up - but not quickly enough to lift the pressure.

The Chinese data backs part of this up. China's imports of Iranian oil dropped 20 percent in April compared with a year earlier. That's a heavy number when you remember China is by far the biggest buyer of Iranian crude - the drop has no diplomatic reasons, it has logistical ones. The ships simply aren't reaching their destination.

"We are holding accountable China-based entities that support Iran," said US Secretary of State Marco Rubio. A line that in any other context would be a diplomatic formality, here put Beijing and Washington in direct conflict through third actors.

For the Balkans, this isn't somebody else's faraway story. World oil flows feed directly into the prices at our local fuel pumps. When Iran can't sell, when China can't buy, everything ends up being settled in Singapore, in Rotterdam, and then in Skopje. The citizen in the Balkans pays a price set at a midnight Security Council session and doesn't know that it's tied to his fuel tank. Geopolitics - it's the economics of the petrol bottle.