You can think of the Dollar's reserve status and the willingness/need of trading nations to hold vast swathes of t-bills or actual dollars as the proverbial big stick that you were advised to walk softly whilst carrying.
It was a weapon of enormous significance, which combined with the predominance of the US in organisations like the GATT,WTO, IMF, World Bank, etc gave the US imperialistic powers over a very, very large portion of the global economy.
You weren't walking softly though, the big stick was being wielded at every opportunity to expand economic hegemony through things like 'deregulation' of markets in economically afflicted nations - and practically every 3rd or 2nd world nation has suffered some sort of economic affliction since the 70's. In one way or another.
There was one direct route to the erosion of that massive stick to beat the rest of the world:
Debt.
With every t-bill issued the stick splintered, cracked and fell apart. Little by little, it's been disintegrating since the late 70's/early 80's. To my way of the thinking, the rest of the world was so used to cowering before the almighty Dollar that it took a long while for the rest of the world to realise that although the owner of the aforementioned stick was still throwing its arms about, the stick had disappeared.
Some USians I've spoken to seem to think that the US is still a global creditor. The US has been a global debtor since the late 80's. Some other nations do owe you debts, but those sums are dwarfed by what you yourselves owe to others.
The power of the stick has been accumulating in China, Japan, the UK(no really!), India, the oil producing states, etc, etc... such that no-one is dominant any more, not the US, not any one of those individual nations who hold dollars.
Although, they all collectively and individually hold a financial nuke in their hands. Should they publicly, rapidly start a large sell-off of t-bills and/or start converting large portions of their dollar reserves into other currencies, then the effect would be dramatic.
The current, massive run towards the dollar and t-bills hasn't really been so much about 'a flight to quality' as 'a massive rush to sell off assets denominated in other currencies so that we can buy assets that let us pay our US Dollar denominated debts'. That enormous bout of deleveraging started last summer and is still going on. It'll probably continue for years.
The problem though, as I think everyone can see, is that even in the face of that massive trade in deleveraging to pay off debt, the dollar still seems to want to fall and the spending/money printing by the FED is not helping that.
Basically, Mr Bernanke is well on the way to something
he stated some 7 years ago (ctrl+f "helicopter"): A helicopter drop of money into the economy to inflate at all costs. The store of value in your money, be damned.
That speech is and should be terrifying to anyone who reads it and wonders what the play book is right now, or where the US and the UK are headed.