What is the US dollar backed by?

As a curious observer of the financial world, I often ponder about the underlying foundation of our global financial system. Specifically, I'm intrigued by the question, "What is the US dollar backed by?" Is it simply the faith and trust of the global economy in the US government's fiscal policies? Or is there a more tangible asset, such as gold or other commodities, that ultimately underpins the value of the dollar? With the constant fluctuations in the financial markets, understanding the backbone of the world's reserve currency is crucial in navigating today's economic landscape. I'm eager to gain insights into this fascinating topic and uncover the true answer to this intriguing question.