First, do not delete the hub. I did this a couple of times and my score took a nose dive. Try "tweaking" the hub by editing the title, and make necessary changes to bring it up to date.As an example, I wrote a hub last christmas on childrens gifts.
Obviously, once the holidays were over, it would not be applicable. I changed the title to birthday gifts and did some editing in the content and images. Worked beautifully.
Write as many "evergreen" hubs as you can.
I've never had this issue, as I don't pursue current events as Hub topics. I do have some seasonal ones (which definitely have their on and off seasons) but mostly I stick to evergreen subject matter as that has been much more productive in the long term. See if you can rewrite it to be evergreen.
If not, deletion may make more sense.
I would not delete them. Other people have asked about deleting hubs before and someone made the point that the hubs could still be of good use. They have advantages because of their age.
Sometimes the search engines look at longevity as a positive in ranking sites. Also, you can use the hubs for back links. I would try changing the hub titles and perhaps re-writing them in a different way.
Also, deleting the hubs may cause your scores to go down. I haven't deleted any of my hubs before. Perhaps someone who has deleted some can tell you their experience.
Either update them, modify them, combine them with other hubs. Or use them as idea generators for future hubs. Perhaps one paragraph can be expanded into a new hub.
Remind yourself to focus on evergreen subjects, unless you enjoy writing personal experiences.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.