The nightmare the international aviation industry has feared for years has come to pass with the eruption of the Icelandic volcano Eyjafjallajokull.
Iceland's apparent isolation from the busiest air corridors in the world counted for little once upper-level winds conspired to blow the volcano's massive plume of potentially damaging ash directly across much of the British Isles and on to parts of mainland Europe.
It seems preposterous for the whole world to be held to ransom by what, in geological terms, is a pipsqueak volcano.
The free flow of people and goods has been massively disrupted around what we are often told has, through air travel and technology, become an increasingly small world, and some airlines struggling to stay in business are expected to fold as a result of their loss of passengers.
On the other hand, the mayhem has, without doubt, been a boon for other parts of the travel industry. Stranded travellers, including Kiwis, in Europe, and marooned overseas visitors in New Zealand will have boosted hotel and restaurant takings and spent more money on taxis, rental cars and on local attractions.
Our expectation to just hop on an aeroplane and go where we like, when we like, is a relatively recent phenomenon. We have become spoilt for choice. Only 50 years ago it was a novelty to fly - in the past week the novelty has been staying on the ground.
European authorities have been reassessing the threat to aircraft and passenger safety and some flights have begun in European airspace as a result.
Airlines are only too well aware of the dangers that volcanic ash poses for aircraft engines, wings and instrumentation, but they have to balance that against the bills that keep piling up while their planes are stuck on the ground.
Although the British Government denies bowing to pressure, a great deal will have been exerted on the authorities to open up the airways, for obvious financial reasons. Airlines will be jockeying for position and will not want to see competitors taking off on some routes when their planes are still at the terminal.
While flight plans have been approved through the margins of a greatly reduced "no-fly zone", the risk of an incident is still higher than for aircraft flying in non-ash conditions.
Modern aeroplane engines chew through around 100 cubic metres of air each second, so even tiny quantities of volcanic ash in the atmosphere can accumulate and cause trouble inside engines.
The repercussions of the eruption have been felt here - our goods have been held up and travel affected. Despite the distance between Iceland and New Zealand, we are geologically similar.
The Ruapehu eruption of 1995-96 affected air travel across the North Island and was a reminder we have more than a handful of volcanoes that could erupt at any time, one of them, Taupo, potentially cataclysmically.
Doubtless there will be good lessons for us from this eruption and Kiwi researchers may well travel to Iceland to study it and the cleanup.
But Eyjafjallajokull's eruption is not over yet. It could go on for months and cause more major disruption to global travel and commerce. It provides a disturbing peek into the future, a vision of what we might expect once oil stocks dwindle and the world gets bigger again.