Dragon's Teeth, or Grow Your Own Army. 3D printed guns are pretty crappy compared to military weapons, but the Wright Flyer was a pretty crappy plane compared to a modern fighter or airliner. 3D printing is in fact increasingly making an impact in industry and the advantage is that a printer that makes a ploughshare today can make a sword tomorrow. Moreover, if equipment (which might be disposable, single-use) can be made clandestinely at distributed locations, logistics takes on new dimensions.
Demonic Possession, or I'm Sorry Dave, I'm Afraid You're Cursed. There's an episode of Mr Robot in which it's demonstrated that smart homes might not be a good idea. If computers can be hacked, then the 'Internet of Things' means that smart appliances can be too. Roombas may not be very effective tanks even with cats riding them, but batteries are potential bombs, which is why you have to take your laptop on board a plane as carry-on luggage and it gets X-rayed beforehand. A co-ordinated cyberattack on a highly-integrated physical (infrastructure) system could not merely shut it down, but repurpose it for offensive purposes.
(50 Shades of) Gray War. There will be no black and white distinction between war and peace. Antagonists will try to seek advantage by crossing traditional boundaries between concepts. As long ago as WWI, Clemenceau said that war was too important to be left to the generals and today 'Hybrid War' is a manifestation of this crossing-over.
Also...
The emergence of a European Defence Force. The Ukraine-Russia standoff right now will certainly rattle European nations however it develops and support for Macron's efforts for a continental force will increase. I don't think that it will appear as a new institution, but emerge from existing structures simply for reasons of time and money. Buzzwords like 'flexibility,' 'commonality,' and 'interoperability' will dominate in planning and procurement. How is this different from an existing multinational organisation such as NATO? First, because it's 'more so' and secondly, it will exist virtually or as potential in multiple national forces, but when an algorithm with the authority of a Field Marshall determines that there's a certain probability that war has already started, then everyone changes their hats, badges, and flags (metaphorically). Intra-EU military procurement will be increasingly and formally co-ordinated and aimed not at reducing strategic arms but building a coherent transnational force: 'If you, a big nation, agrees to build an aircraft carrier, then we, a small nation, will agree to start producing/buying IFVs.'
Many of you who live in large countries with military forces that have wide capabilities may not appreciate this approach, but as a small country, New Zealand has had to make ruthless choices about what it can afford. We disbanded the combat wing of our air force decades ago, but retain the maritime patrol and logistics/transport wings. A navy that would serve our national interests best would consist of many River-class patrol boats and be deployed for fisheries and customs protection along with SAR. However, we have frigates that were procured (in a joint venture with Australia) specifically so that they could operate alongside other navies or substitute for ships in other navies that were called away to combat.
How would it work in practice? Dunno.
[MEDIA=youtube]m_MaJDK3VNE[/MEDIA]
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