They don't need armies, they need allies. The problem then becomes finding an ally with a strong army but without a strong inclination to use said army to take over your micronation.
The ally needs some motivation to take on someone else's existential threats as their own. Lots of treaties and posturing may dampen would-be aggressors' motivation, but as the USA has demonstrated of late re: Ukraine vs Russia, all too often promises of military protection don't mean $#!^.
