I just saw this question, which is a kind of plot-hole question, if you want. The question, being about "Hunt for Red October", has the tags
cold-war (which the movie's story is about in general), though it is not really a question about the movie's overall story, one of those topics or movies about those topics in general (it is somehow related to submarine technology, but this is no Q&A site about applied nuclear physics, and it's more of a plot-hole question really). So I think those tags are not really fitting here and such behaviour could lead to a tag explosion of the question (though I know it's limited to 5, but even worse, which to pick from a large variety) or maybe the site?.
So is this appropriate for this question? Is it only appropriate if the question really has a connection to these topics? Or is it not really fitting at all to intoduce such "content theme" tags, as there are movies about everything but often the question is not about space travels in general, but about "Star Wars" or maybe Science Fiction in general (genre tags are a good idea, of course)?