As Christians, we hope for the next world - for life beyond the portal of death. It is this hope that prevents despair; and this hope is the natural (unforced) consequence of trust in Jesus Christ; which is trust that he can and will lead us to resurrection into Heaven; also trust in God (the creator) who will ensure that we are able to do this, if we choose.
But what of hope in this world and for this-world (the temporary world of our mortal life)? Well, such this-worldly hope is not necessary. I see no reason why a Christian must live in hope of betterment of this-world.
The main thing that can be said in favour of hope in this-world is that we never truly know all the relevant information, nor how other people will choose; thus we never know for sure that the worst will happen. This is the best argument for never-giving-up.
We may calculate that there is zero hope; but our calculations may be defective and will certainly be based upon incomplete - hence distorted - information; plus at least some of the information in our calculation will be false - lies or misunderstandings.
However, there is nothing wrong with a Christian having no realistic hope in this-world - so long as it does not lead to despair and giving-up. A Christian might perfectly well write-off this world, and work for the next.
But a hope-less Christian would also need to recognise that - in the meanwhile - there is a reason for his being alive, here and now, in the situation he actually is-in; and that therefore there is something important that he ought to be doing - some lesson that he yet needs to learn.
The point I wish to make here is that I think it is probably a waste of time for Christians desparately to try and generate some grounds for hope in this world - but I would observe that many Christians (including myself) are prone to do this. I mean, we tend to use the wriggle-room of uncertainty about the future to insert some grossly improbable scenarios about what might happen - like tens of millions of people suddenly becoming Christian (at the last minute).
Of course it might really happen, such is not precluded --- but really it is futile to waste our time on such scenarios - and certainly we should not Pin Our Hopes upon them - or else despair is even more likely.
I think it would be better to say something like: I see no realistic hope for the world from our present situation and on current trends; but I might be wrong... And leave it at that.
If we try to define one or several of the most probable directions of the (highly improbable) saving of this world, and if then we then put most of our (finite) resources of time and work into accomplishing this remote hope - then we are probably misdirecting our efforts.
When the future of this world is evaluated as hope-less, this means it is unworthy of any specific hope; and it is wrong to push for (almost-certainly) futile hopes - when there are so many other things that need to be done, that we personally can do, and which have much better hopes of yielding fruit.
Our proper task is most likely to be something specific and close-to-home, and directed at preparation for Heaven, which has reasonable hope of yielding fruit --- rather than some-thing directed at saving a world/ civilization/ nation etc. that (our honest evaluation tells us) does not want to be saved and very-probably is not salvageable.