The Chairman of the Joint Chiefs of Staff has just described the four best military options to you. Your options are to put US conventional forces on alert, send the US Navy into the Formosa Strait between China and Taiwan, send a small number of US troops to Taiwan, or put US nuclear forces on a heightened state of alert.
Putting the conventional forces on alert will demonstrate the US interest in resolving the dispute without having to deploy US men and women to the region. China will hopefully understand the US intent and back down.
Sending the Navy into the Formosa Strait will physically halt China from attacking Taiwan; however, this could cause China to become more aggressive, and a Chinese attack would place China and the US in a full-scale war.
Sending troops to Taiwan would demonstrate more of a US commitment than simply putting them on alert, although a small force probably would not be able to hold off a large Chinese attack.
Putting your nuclear forces on alert would definitely demonstrate that the US will not let Taiwan fall into Chinese hands. However, China has its own nuclear arsenal that it capable of reaching the US West coast. Nuclear threats could simply expand the boundaries of the crisis.
The Chairman does not advise one way or the other. It is up to you, you decide to...