[lvlrsSTI]

If it can happen, it would have happened long time ago.

Why not.

1. If not USD what currency? For example Singapore dollar pool would be too small. US economy is largest in the world and well established. Others are Chinese Yuan, Euro and Japanese Yuan.

2. Japanese Yen has disadvantage of being too small I'm circulation given Japanese economy js 20% of US.

3. Euro is probably the best alternative to USD as combined Euro economy is same or larger than US.

4. The Yuan is not possible because it has currency controls. The same reason why rest of the world use WhatsApp and China use Wechat. The currency is divided into onshore Yuan and offshore Yuan and the currency control is in place because Chinese govt is afraid of currency speculators. The Chinese also do not have free trading of Yuan unlike US Dollar, they artificially set exchange rate. While US$ is freely floated.

5. Despite its huge debt and deficit US$ remains king due to widespread acceptance.

Whatever it is, USD domination will be over soon, some countries will use Euro, others will use RMB or Yen for trading.