Hong Kong has been gripped by protests and violence since mid-June, with many in the city blaming this on external interference. China has repeatedly criticized the United States for meddling in Hong Kong's internal affairs.

In March, U.S. Vice President Mike Pence met with Hong Kong's former Chief Secretary Anson Chan. A few days later, U.S. House of Representatives Speaker Nancy Pelosi met with opposition lawmakers Dennis Kwok and Charles Mok. The opposition leaders' trip to the U.S. also included meetings with congressional committees and bar associations.

In May, Pelosi and U.S. Secretary of State Mike Pompeo met with several opposition figures, including Martin Lee, Lee Cheuk-yan and Nathan Law.

In June, U.S. Congressmen Marco Rubio and Jim McGovern reintroduced the so-called "Hong Kong Human Rights and Democracy Act."

Pelosi called the demonstrations in Hong Kong "a beautiful sight to behold."

In July, Pence and Pompeo held meetings with pro-opposition media tycoon Jimmy Lai, discussing Hong Kong's amendments to the Fugitive Bill.

And in the midst of the unrest, Julie Eadeh, who works at the U.S. Consulate General in Hong Kong, was filmed meeting with opposition figures Martin Lee and Anson Chan. She also met Hong Kong protest leader Joshua Wong.

In September, the U.S. Congressional-Executive Commission on China held a Hong Kong-related hearing and invited Joshua Wong and fellow protest leader Denise Ho to testify. 

In October, U.S. Senator Ted Cruz met with Anson Chan and Jimmy Lai in Hong Kong and wore black to show support for protesters.

On October 15, the U.S. House of Representatives passed the so-called "Hong Kong Human Rights and Democracy Act of 2019," which was later passed by the Senate on November 19.

There have also been reports of U.S. financial support for protesters. One of the most notable sources was the private foundation "National Endowment for Democracy," which the Global Times says is backed by the U.S. Central Intelligence Agency. According to the foundation's website, it has granted millions of dollars to the Solidarity Center and other organizations in Hong Kong.