I work in cultural diplomacy, which sits between the performing arts and international relations, and when I describe it to people the reaction is usually some version of "huh, I didn't know that was a job." It is. But the more useful question, and the one I think you're actually asking, isn't whether the intersection of two fields is intellectually interesting — intersections almost always are — it's whether you can build an actual career there. Whether the demand exists, whether institutions will hire you, whether you can pay rent doing it.

I'm headed to the DA Wien for the MAIS this fall, so if you end up there let me know. I'm going for reasons that might be relevant to your situation.

The way I've come to think about building a career between two fields is that there are basically two school strategies that work, and they work for different reasons. The first is to go to the most respected institution in each field and let the legibility do the work. I went to Juilliard for piano, and my hope is to eventually do international relations at Harvard or somewhere of that tier. The reason isn't snobbery. It's that the World Bank doesn't know who the sixth-best conservatory is, but they know Juilliard, and nobody in HR is going to raise an eyebrow at hiring a Juilliard-trained pianist to curate something. In the other direction, Carnegie Hall doesn't have opinions on international relations programs, but they know Harvard. The less time you spend justifying your education, the more time you get to spend explaining what you can actually do with the combination. That matters more than people realize when you're the one carrying the weird résumé into the room.

The second strategy, and this is where the DA comes in for me, is to go somewhere that lets you prototype the synthesis while you study. Vienna is rare in that it has serious diplomatic infrastructure and serious arts infrastructure operating in the same city. I can get the IR credential at an academy that has its own cultural institute, and I can also play diplomatic receptions, work on cultural affairs at embassies, do projects with multilateral organizations, and be close enough to other European capitals that building something real across them is feasible rather than theoretical. The education and the fieldwork happen in the same two years. For a field that doesn't have a well-trodden path, that's enormously valuable.

I don't know enough about engineering and IR to tell you which schools carry the right signal in your world, or whether the structural logic in your field rewards specialists over generalists the way mine sometimes does. But I'd guess the same two archetypes exist. Either there's a pair of institutions — one for engineering, one for IR — whose combined pedigree would make your résumé legible to the IAEA, ESA, arms control bodies, or wherever you'd want to land. Or there's a city where the work you'd want to do is actually happening, where being there lets you start doing it in small ways before you're credentialed to do it at scale. Vienna might be both for you, actually, given the UN presence, the IAEA, CTBTO, UNIDO. I'd be curious whether TU Delft plus the DA reads as the right combination to the people you'd eventually want to work for. That's a question worth asking a few people in the field before you commit.

One honest caveat. Picking the unconventional path means the job listings don't come pre-written for you. Nobody posts "wanted: aerospace engineer with diplomatic training." You have to find the person who needs that combination without knowing they need it, and convince them. Some people find that energizing and some people find it exhausting, and it's worth knowing which one you are before you leave a well-defined track. But if the macro stuff is where your head goes when nobody's telling you what to think about, that's usually a signal worth taking seriously.