I can unreservedly recommend
this analysis of China's strategy by H. R. McMaster, a retired United States Army lieutenant general, who is a former White House national security adviser.
China has become a threat because its leaders are promoting a closed, authoritarian model as an alternative to democratic governance and free-market economics. The Chinese Communist Party is not only strengthening an internal system that stifles human freedom and extends its authoritarian control; it is also exporting that model and leading the development of new rules and a new international order that would make the world less free and less safe. China’s effort to extend its influence is obvious in the militarization of man-made islands in the South China Sea and the deployment of military capabilities near Taiwan and in the East China Sea. But the integrated nature of the Chinese Communist Party’s military and economic strategies is what makes it particularly dangerous to the United States and other free and open societies.
It's a long piece - so make yourself a coffee first.