From Joseph A. Bosco, senior associate at the Center for Strategic and International Studies:
Effective deterrence requires both the will and the capabilities — and the proper communication to the adversary that we are armed with both.
…several U.S. China experts publicly say otherwise, that the U.S. would not and should not intervene. Such talk, taken with other factors, encourages China’s planners to reach the same conclusion. I believe they are wrong, but a major strategic miscalculation is in the making — not because of U.S. capabilities, which are far more than adequate, but because of the perception of the lack of U.S. will.
Without the credible threat of war, the world becomes a dangerous place, with rogue states invading other territories in the belief that a response is unlikely.
As Henry Kissinger says of the Korean War, “We did not expect the attack; China did not expect our response.” Of such miscalculation, devastating wars are made.
It is evident that US foreign policy is based on President Theodore Roosevelt’s maxim: “speak softly, and carry a big stick.” But you must demonstrate that you are prepared to use the stick for it to be an effective deterrent.
Margaret Thatcher (Statecraft: Strategies for a Changing World) put it in a nutshell:
“Interventions must be limited in number and overwhelming in their impact.”
Read more at China's Deadly Miscalculation in the Making | RealClearDefense.