I'd never heard of such a thing before. Seems a bit worrying, but whatever. It's not like I have to live in your country.
I wonder why they need it at all, really. If it's mandatory, your consent doesn't mean anything. You'd still probably see thousands upon thousands of draft dodgers if they tried to introduce the draft again, forced promise or no. And as for them needing it to check who's eligible for the draft, can't they just use birth records for that?