In the 19th century Great Britain invested heavily in the United States and elsewhere in the western hemisphere. In the 20th century, under the label "dollar diplomacy," the United States deepened its economic involvement in Latin America and elsewhere. Today, the Chinese are following the same playbook.
Defense One has a comprehensive look at what is happening. I think the Chinese actions are opportunistic rather than threatening, but if the United States fails to live up to its leadership role -- such as by the congressional refusal to adopt IMF reforms -- the baton will shift to Beijing.