I wrote about this on the Project Reason forum, and I was wondering what your thoughts are. I understand this is a very complex issue - I’ll try to be as concise and to the point as possible.
Secular beliefs and values are derived from a lack of religion. One key difference between secular ideas and religious ideas is that religion states there is life after death - secularism states no such thing. One has to operate under the assumption that death is a state of nonexistence. The trouble here is that any meaning that life has vaporizes once death occurs to the point where a dead person is incapable of caring about the things they cannot experience. This creates a huge problem for the secularist - the problem of caring about what happens in the world once their death occurs.
It is my view that every secularist finds some way of either ignoring or denying the inevitability of death in order to function normally (that is, to care about the actions they take in their lives). A religious person fares no better - they take the equivalent of a placebo and mock the secularist for not having a cure. I believe that we, as a society, are nearing the age where we find a cure. This is important - because real, tangible immortality will destroy religion.
Why does immortality destroy religion? In a large part, it replaces religion. Promises of immortal life after death seem childish compared to having immortal life during life. Hard liners will still cling to their old beliefs - but when two populations exist in one habitat and one population is immortal, natural selection dictates that the immortal population will grow faster than the mortal population.
Why should we care? Because immortality is closer than you think. Anti-aging is the best possible avenue to immortality and we are learning more about it every day. Anti-aging prevents not only the inevitable death from age society is so accustomed to, but also a large number of compromises and scientific barriers dissipate once you halt aging. Probably the most popular compromise is that people think living forever means living in a decrepit state - but anti-aging (and possibly reverse-aging) immortality would lead to living forever while maintaining good fitness. It also seems like living forever would expose you to new and unforeseen diseases which might be incurable - except that if you halt aging you not only halt slow body degradation but all age related diseases as well.
I know that I probably will have to clarify a great deal of assertions made here but the main point here is that tangible immortality is possible, and such immortality is necessary for existential stability of a secular individual.