How does fentanyl get into the US?

Fentanyl, responsible for over 74,000 American deaths in 2023, primarily enters the US through Mexico using chemicals sourced from China and increasingly from India. Mexican cartels manufacture the drug using Chinese precursor chemicals, with 98% of US seizures occurring at the southwest border, while China maintains it has strict drug laws despite evidence of companies knowingly selling fentanyl-related chemicals.