It's the same situation in most countries around the world, forced by global circumstances and changes to use the dollar in exchange for American protection.
Governments are rarely forced to follow some other country they just get development help and have to play by the rules. Still the trust in a currency is given and taken by the very people a government is servant off. They just swapped rules and became rulers. Than they discover the US$ so it good for them to de-valuate their own. Why due to paying wages in their currency. Most cynical governments collect in $ and pay in their currency.