![Why It Is So Difficult to Stop the Flow of Fentanyl Into the U.S. Why It Is So Difficult to Stop the Flow of Fentanyl Into the U.S.](https://i1.wp.com/static01.nyt.com/images/2025/02/05/multimedia/05mexico-fentanyl-explainer-1-pvqg/05mexico-fentanyl-explainer-1-pvqg-facebookJumbo.jpg?w=600&resize=600,400&ssl=1)
Why It Is So Difficult to Stop the Flow of Fentanyl Into the U.S.
When President Trump threatened to impose steep tariffs on Mexico, Canada and China, he blamed these three countries for enabling the flow of fentanyl into the United States and fueling what officials have called a national emergency. President Claudia Sheinbaum of Mexico swiftly pushed back on Mr. Trump’s suggestions that her government colluded with drug…