Popular with whom? Buddhism has basically replaced all other religions with the intelligentsia in the USA. Christianity is not take seriously any more, for fairly obvious reasons. But across the world Evangelical Christianity is grown as Catholicism loses its grip. In other words the reformation is just now reaching some places on earth. Buddhism is older than Christianity by about as much as Christianity is in relation to Islam. So Islam is just now reaching the reformation period, which by the way was when there were a lot of wars between christian groups. Buddhism was pacifist from the beginning but it is long past being something to fight over, and that is something that appeals to many who are sickened by the wars of the twentieth centuries which were ideological rather than religious, but who is to say ideologies are not just religions in other form, i.e. secular religions.
In reply to a comment asking me to support my assertion that the Intelligentsia in the USA. Of course, I don’t have any statistics to support my case. But what I have is a deep reading of the tradition which basically amounts to an attempt to understand Buddhism, Taoism and Sufism and watching what has happened to Buddhism over the years. The key event was the exile of the Tibetans, which gave legitimacy to the Buddhist movement in the USA. Basically Tibetan Buddhism has transplanted itself to the USA. The Dali Lama is seen as an acceptable alternative to what appears to be a Nazi Pope. But the key point is the extent to which Americans have taken on Buddhist scholarship under the tutelage of the transplanted lamas. Now when you combine this phenomena with the fact that Tibet had an unbroken Buddhist tradition, with deep scholarship we get a very powerful intellectual combination, which has become growing movement in the USA. Disenchanted with the Dualistic Western tradition, many are turning to this alternative because it is a living tradition, going back to the Buddha which has perhaps deeper philosophical roots than the Western tradition. We are talking about an unbroken tradition going back to 600 BC or so. The Western tradition seems like an adolescent in comparison. Up in those mountains in Tibet amazing things were happening that we are only now learning about as many major texts are being translated. One of those things is DzogChen. In terms of personalities we have Dzong Ka Pa on the one hand and Mipham on the other. These were amazing Buddhist scholars. Interestingly Dzong Ka Pa thought that consciousness was not reflexive, and Mipham defended the reflexivity of consciousness. Buddhism other places has have its ups and downs but when it mostly died out in India it lived on in Tibet. However, we do not say that it survived in any pure form. Tibetan Buddhism is a real mess. But it is a fertile mess mixing shamanism with exalted meditational states, and sublime philosophy. Much more sophisticated philosophically than Western Dualism which is about as crude as you can get even though it has its own interesting moments. Western Philosophers don’t know anything about Buddhism, and particularly nothing about Tibetan Buddhism. So all this has passed by unnoticed by the Western Philosophers. But I believe that others have taken note. Personally I think that the success of Tibetan Buddhism is that it has monasteries, and Lamas and something like a Pope and so we can understand the structures even if we do not understand the ideas. And our desire is to escape the Catholic influence (read inquisition, and crusades, and destroying cultures though the manifest destiny of colonialization) that they are willing to embrace a Buddhist Pope. Once we have a lot of texts translated and a gaggle of American born Tibetan Buddhists I think things are going to get really interesting, because the level of intellectual sophistication and the depth of their tradition is hard to match. About all Western dualism can do is ignore it. But there is a good chance that the populace will take it seriously, because it offers a genuine nondual alternative with its own tradition. And the kicker is that Buddhism itself is a heresy of the Indo-European tradition (cf Hinduism in India) and so it is well equipped to deal with dualism, because this heresy grew out of the Indo-European roots. Most of the Western Intelligentsia are willing to take this form of Buddhism seriously while they no longer are interested in Christianity. Christianity is basically spreading out its evangelical tentacles around the world, while nondual Buddhism comes home to roost here at the center of the global empire. The decisive difference is that Buddhism is considered spirituality and not a religion, as such. This is because Buddhists don’t care what else you claim to be, as long as you put in your time meditating. The death knell of Christianity occurred when you had Zen Catholicism. Non-dual paths are not exclusionary. What ever you call your self or think you are when your brain is stilled and experiences prajna everyone is the same. My wife showed me a cartoon of a Zen Monk getting a card which said, “Not thinking of you.”. That about sums it up, Buddhist spirituality, not as a religion, is seen as intellectually acceptable by many of the Intelligentsia. This is because there is a deep suspicion concerning any mass movement after a century of fighting ideological and thus perverted religions in the twentieth century. Buddhism fits well our capitalistic individualism as consumers in a mass market. As Adorno says in Negative Dialectics the powers that be are happy if their intellectuals stop thinking. That is exactly what they want them to do.