Answer: President Biden did not "let" President Tsai Ing-wen of Taiwan come to the United States. As the President of Taiwan, President Tsai has the right to travel abroad and meet with leaders of other countries, just like any other head of state.
It is important to note that the United States has maintained unofficial relations with Taiwan for decades, while officially recognizing the People's Republic of China as the sole legitimate government of China. In this context, visits by Taiwanese leaders to the United States are not uncommon and are seen as a way to maintain unofficial ties and promote cooperation between the two sides.
It is also worth noting that the United States and Taiwan share many common values and interests, including a commitment to democracy, human rights, and regional stability. As such, it is natural for the two sides to engage in regular dialogue and cooperation.
Step-by-step explanation: