Hi OP, KCL War Studies academic here (MN regular but have name-changed for this). Glad to hear your DD is thinking of applying to us!
As other people have said, we have a global reputation as a centre of expertise in our field(s) - though on the downside, yes, the department's performance in the Tolstoy Cup over the years has left a lot to be desired. The department and the degree are very well known, and a major asset when it comes to jobs - both because of our reputation and because of the skills our students develop (again, with the lamentable exception of football).
One of the great things about the degree, and the department is that precisely because it's not a standard History or IR degree, it tends to attract people who are genuinely interested in the subject. That makes for a much better experience for students (and for us).
The degree is a mix of several disciplines: history, IR, security studies, strategic studies are the most obvious ones. Students can study a huge range of things, from the history of naval warfare to international law, cybersecurity, the conflict in the Middle East, Russian foreign policy, disaster response, conflict journalism, war and and gender, the history of nationalism, security in Latin America, early 20th century international history, and a lot of other things. You can get a sense of the variety of what we do and teach from our War Studies podcast series.
Not many of our students go into the armed forces. Most of our students seem to go into the normal Russell Group social sciences/humanities jobs (law, management consultancy, the civil service, etc) but some end up in areas connected to the degree - security research analysis, journalism, working for organisations like the UN, the OSCE.
If you have any questions about the degree, the department, or KCL, happy to try to answer them here, or you/your DD can DM me.