The US dollar has traditionally been the global standard for business transactions. This gives the US a strong hand in policing international trade, allowing it to monitor and control many financial dealings. However, some countries are now moving away from using the US-dollar system.
Instead, they’re turning to China’s yuan as their main currency for international trades. By doing so, these countries weaken Washington’s ability to enforce its rules and regulations. This is a significant shift in power dynamics, with the US losing control over how global trade operates.
Source: https://www.wsj.com/world/what-to-know-about-how-iran-uses-chinas-currency-to-weaken-u-s-power-38fcf046