At a tl;dr level - getting discharged from basic training for being grossly incompetent is a far easier task to handle than evading a draft and ending up with a gaping butthole in prison.
Unless the country that you live in provided you, as a citizen, with such unparalleled advantage relative to the rest of the world that you feel genuinely compelled to enlist in the armed forces, there's no logical reason why any sane male would sign up for conscription without legal coercion.
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I registered for the Selective Service when I turned 18 as a prerequisite for my FAFSA. With that said, I wouldn't necessarily be enthralled with conscription should it ever happen to me. I'll do as I'm legally obligated, but no more. It's quite a shame too, because I grew up with this idea that there was no greater honour than to fight, bleed, sacrifice, and die for the country that birthed and raised you. Unfortunately... I don't consider the USA a country worth dying for in the line of duty. As blasphemous as this sounds, hear me out:
If I were 18 at the onset of WW1 when Woodrow Wilson started the recruitment drive, I would've signed up without hesitation and I would've gladly laid down my life for the USA at that point. If I were 18 at the onset of America's involvement in WW2, I would've gladly signed up for either the European or Pacific Theatres without any real care for which side of the world I'd be deployed at. In those situations, the USA was a neutral party whose NAP was violated (albeit on a far smaller scale compared to the collective NAPs in Europe that Germany violated in both wars). From WW2-onward though, this is where shit becomes harder to justify:
I damn sure wouldn't have joined the Korean War because this war happened during a time when Harry Truman himself genuinely considered nuking the Korea/China border under MacArthur's recommendation. Douglas MacArthur was a decorated war hero, but if I were a private or a corporal and I was serving under him, I'd definitely be thinking he let the rush of Hiroshima and Nagasaki get to his head. Also, let's not forget that the most recent war the USA fought prior to this was five years ago at that time. The USA came out of WW2 relatively unharmed, but we were neck-deep in debt at the time with the Marshall Plan too. How could we have even won the Korean War if we still lost a ton of men that we can't easily replace?
Vietnam War? Same as I said otherwise: I'd vehemently object to the war on principle, but if I was drafted, I'd just have to grit my teeth and bear it as best I can. No doubt that I'd be praying for one of two things: a legally binding excuse for the military to send me home OR a swift and merciful death.
Then we have all that bullshit in Lebanon, the Israeli sinking of the USS Liberty, Bay of Pigs, Dominican Civil War, Cambodia/Laos Civil Wars, the invasion of Grenada, Libya, Panama, Desert Storm, Mogadishu, Yugoslavia, Haiti, etc. ALL of that nonsense is BEFORE we even get into the sheer clusterfuck that is the 21st century thus far. If I was born before 1945 and I had a chance to fight in WW1/WW2, I would've laid down my life for the USA with no questions asked.
However, I'm a distant post-war child born to immigrant parents in the USA. My attachment to the USA is extremely deep because the quality of life I enjoy here (even with all the bullshit under Biden) is far superior to anything I would have in my country of origin. I want to lay down my life for my country. I want to serve the nation that made me into the educated man that I am in the best way possible.
But how can I join the armed forces of a nation that no longer defends itself, but rather feels the urge to act as the global tard police? I don't wanna wrangle tards in other parts of the world; I wanna defend my country. What tangible threat do the dribbling, drooling tards in the rest of the world pose to us?