You could say that Taiwan is caught in a pincer attack. As far as heroin goes, the main supplier to Taiwan is the infamous Golden Triangle (lawless territory where Burma, Thailand, and Laos come together).
以海洛因來說，鼎鼎大名的「金三角」（緬甸、泰北、寮國交界的三不管地帶）是台灣貨源的主要供應地。