Nancy Pelosi, a Democrat from California, is speaker of the House of Representatives.

Some 43 years ago, the United States Congress overwhelmingly passed — and President Jimmy Carter signed into law — the Taiwan Relations Act, one of the most important pillars of U.S. foreign policy in the Asia Pacific.

The Taiwan Relations Act set out America’s commitment to a democratic Taiwan, providing the framework for an economic and diplomatic relationship that would quickly flourish into a key partnership. It fostered a deep friendship rooted in shared interests and values: self-determination and self-government, democracy and freedom, human dignity and human rights.

And it made a solemn vow by the United States to support the defense of Taiwan: “to consider any effort to determine the future of Taiwan by other than peaceful means … a threat to the peace and security of the Western Pacific area and of grave concern to the United States.”

Chinese ambassador: Why China objects to Pelosi’s visit to Taiwan

Today, America must remember that vow. We must stand by Taiwan, which is an island of resilience. Taiwan is a leader in governance: currently, in addressing the covid-19 pandemic and championing environmental conservation and climate action. It is a leader in peace, security and economic dynamism: with an entrepreneurial spirit, culture of innovation and technological prowess that are envies of the world.

Yet, disturbingly, this vibrant, robust democracy — named one of the freest in the world by Freedom House and proudly led by a woman, President Tsai Ing-wen — is under threat.

In recent years, Beijing has dramatically intensified tensions with Taiwan. The People’s Republic of China (PRC) has ramped up patrols of bombers, fighter jets and surveillance aircraft near and even over Taiwan’s air defense zone, leading the U.S. Defense Department to conclude that China’s army is “likely preparing for a contingency to unify Taiwan with the PRC by force.”

The PRC has also taken the fight into cyberspace, launching scores of attacks on Taiwan government agencies each day. At the same time, Beijing is squeezing Taiwan economically, pressuring global corporations to cut ties with the island, intimidating countries that cooperate with Taiwan, and clamping down on tourism from the PRC.