Ymb,
you say
“never in the history of golus was there an army to defend ourselves”
A very untrue statement maybe you should go check but their were many places were Jews had armies post exile.
lets get down to the real problem here its that the chariedim feel that they cant serve in a army that is part of the “illegitimate” state.
Although can you make sense of this, the Chashminoim were a illegitimate Jewish state. yet we look back on Jewish history and still remember them for doing much good(albeit without a Davidic leader) the problem is to much superstition has filled the air over many generations yes at the moment we don’t have a Davidic dynasty in rule it doesn’t mean that you can throw away the obligation to defend Jews.
But then you will say we have a obligation to learn. i say why cant you do both. And maybe have a few people who can be exempt from military duty to learn but only a very few. In Jewish history not every one was fully learned as in todays society only a few were well knowledgeable the only people who should be exempt from military service are those who are exceptional at learning and who live what they learn, not an everyday joe schmoe who sits and goes i”m learning therefore im exempt. Thats irresponsible