My cheery little thoughts on this:
We don't know who attacked the two oil tankers on June 13th, or what they used. Personnel on board reported a drone attack, and outsiders blamed limpet mines.
Who did what to whom is really a little inconsequential.
The real issue is that the closure of the the Strait of Hormuz would be catastrophic for the world economy.
Most economies are based on the twin ponzi schemes of economic growth and population increase. We know both can't continue indefinitely. The question is how well we will manage a slow deflation of our economic bubbles.
Closing the Strait would effectively be sticking a pin in them. Iran doesn't have to physically close the Strait. Just the threat to sink any ship travelling through there would be enough to drive insurance premiums up to the point where shipping through there simply stops.
If you live in a country that relies on imported oil to make your economy work, there comes a point where economic activity stops if the price goes too high. The resulting stock market crash will wipe out your pension schemes (check if your pension scheme relies on the stock market. I shifted mine out away from that some years ago). What will happen to your population and economy when pensioners have no income, all service jobs disappear and food distribution systems crash?
Hint: when the Soviet Union dissolved most people without a secure job perished.
Added to the mix is the likelihood that China and Russia won't want to see Iran fail. Who knows.
I don't think the effect of population growth on an economy is that cut and dry.
Although it is true that current trades are pointing to some countries having decreases in population, this is mainly due to the industrialization of those countries and the mass population moving into cities, which are safer. Since cities are generally safer and the amount of manual labor required to survive in a city is significantly less than in a country side dependent on subsistence farming, there is less of a need to have many children. Population growth is certainly going to slow due to this.
However, although the decrease in the speed of population growth will certainly effect GDP, perhaps even lowering, a couple of things need to be first taken into account before one can assume this would be negative. First, having a smaller GDP with a smaller population does not necessarily mean that the future population will be poorer per capita. It could be that the population decreases at a faster rate then the GDP, which would have the effect of increasing per capita GDP. Second, since cities are safer, and less physical energy and time is required to sustain yourself, generally speaking people growing up in cities (or at least in industrial economies) tend to be more productive. Increase in available energy (other then physical) is certainly a reason for this, but also less time spent on farming gives people more time for study and advancement of skills. So, with population decreases due to industrialization, the average person will actually become more productive, leading to an increase in per capita GDP as well.
So, if the population does decrease, this does not mean it will effect the economy in a negative way. Sure, maybe total GDP will decrease, but more then likely per capita GDP will continue to increase.
Now, I would agree that pension plans based upon future retirees paying in for current retirees to take (like traditional union pensions and social security) are indeed based upon the idea that the next generation will always be slightly larger then the previous one. They can only work if this is the case. So for those of you depending on traditional pensions or SS, you're pretty screwed if the population starts to decrease or even stagnant.
