“Ammunition is really a key constraint for a lot of European militaries,” said Ed Arnold, a research fellow for European security at the Royal United Services Institute in London. “We just don’t have enough ammunition. So forget about the end use of what mission this might be on, and what we want to do with it. It’s got to exist on the shelves first. That is quite expensive initially, to reopen production lines.” “But there’s no real alternative,” he added.