Geopolitical strategist Peter Zeihan talks about the concerns over dedollarization. Zeihan states that there are three factors for a global currency and why the United States dollar is the only currency right now to have all three:
"#1 Size - To be a currency of exchange, trade, and reserve, a currency must exist in a massive volume. Only four currencies meet the size requirement: Dollar, Euro, Yen and Yuan.
#2 Access - You need to be able to get ahold of a (nearly) unlimited supply of said currency at the drop of a hat. The Dollar comes out on top in this category, with the Yen and Yuan unable to provide the necessary level of access.
#3 Trust - You must feel secure that the chosen currency is a safe store of value and that the government will not intervene. This makes the currency a subset of trade, and if the country in charge wants to micromanage the value on a daily basis, it won't work."