A hypothesis to mull over: current popular attitudes toward Buddhism and Islam are two sides of the same phenomenon constituted by the needs of Christian (and Christian-derived) America’s imagination. Islam is understood as the demonic other, a dangerous group fanaticism (Islamo-fascism, etc) that twists the familiar pattern of moralistic monotheism to produce enemies of America. Buddhism is constituted as the angelic other, a peaceful individualistic path of private meditation that is so different from Christianity that it poses no boundary threats. Buddhism in these narratives is the liberal, benign foreigner that presents no danger; Islam is the encroaching aggressor with a closed mind that can be neither opened or understood. Neither depiction is even remotely close to capturing the general nature of either religion.
Buddhism receives almost universal good press in America, while Islam receives almost constant bad press. The reasons for this are not simply that some practitioners of Islam have attacked Americans, at home and abroad, or that Islam is linked to violent struggles in some parts of the world. After all, Buddhism is also linked to violent struggles and has plenty of blood on its hands, historically speaking, and Buddhists have supported armed conflicts with America within living memory, if not at this particular moment.
The answer seems to be that Buddhism is weak, while Islam is strong, and that is why Buddhism is perceived postively and Islam is believed to be wicked. Buddhism poses no threat, military or otherwise. Buddhism has been in a sharp numerical decline for well over a century. Islam is the world’s fastest growing religion, currently number two in terms of size. Buddhism lags in perhaps fourth or fifth place. Buddhism is growing in the United States, but there are probably twice as many Muslims here as Buddhists, and again, Islam is growing more rapidly.
This is meant as a general thought exercise, not hard data. It seems reasonable that how we construct other religions is based at least as much on how much they challenge or frighten us (often based on current social/governmental factors, rather than religious one), as opposed to any particular qualities actually inherent in those religions. Islam was our ally during the Cold War; Buddhism our enemy during WWII. Should Buddhism become strong once more, it might lose much of its current favor in the United States, and if Islam begins to lose its ability to aggressively assert its own agenda(s) in the face of American desires, it will probably come to seem more inherently benign once again.