An interest rate hike in the US dollar means that the US dollar supply will decrease (just as the amount of money in the market will decrease if our banks raise interest rates on deposits and loans), and the US dollar will appreciate. At this time, if you invest in the United States, the dollars you earn will be more valuable, so that all the funds in the international market will begin to be transferred to the United States. Before transferring to the United States, assets of other countries must be converted into dollars before investing in the United States, thus forming the "selling assets for dollars"