Speak for yourself about what's moral and immoral.
I thought I was.
I don't see conscription as an absolute evil like you do.
Then feel free to frame your position based on your views.
I see it as a relative evil. Conscription is sometimes the lesser evil. For instance, conscription in the UK, the Soviet Union, and the United States during WWII probably has a lot to do with why most of Europe isn't part of a greater German Reich today.
And WWII wouldn't have happened without the conscription-fueled slaughter of WWI.
My position is that if a cause is worth dying for, then you can convince volunteers that it's worth dying for. And if their sense of patriotism and duty isn't enough, entice them in other ways: money, for instance. Or show them that their families will be taken care of while they're away.
Life is not always Sunday school simple and conscription is not always the greatest evil. At least that's my take on it.
I don't claim that life is simple; I just draw a line at slavery.
People can - and have - come up with justifications for all sorts of horrible things from nuclear weapons to carpet-bombing to battlefield rape to conscription. Different people will draw their line at different points. All of them were done by the Allies in WWII. All of them played a role in the outcome of the war. How would the war have played out without any one of them? It's hard to say.
Having said that, the conscription of men to fight the Viet Nam war was indeed evil in my opinion, but then that fact it was evil is not at all relevant to the point being made in the OP, is it?
If the conscription is evil, then avoiding it is morally permissible. The question then is whether avoiding the draft for onesself creates an obligation to help others avoid it. I'd personally say that helping others in this regard is morally praiseworthy but not morally obligatory.