Minority Republican: [That’ll destroy the nation if they use every able bodied man.]
https://en.m.wikipedia.org/wiki/World_War_II_casualties#Total_deaths_by_country
Somehow the German nation not only survived, but went from strength to strength. The Soviets used every able-bodied man in in WW2. Ukraine lost 4% of its people (8% of its men) as military dead, 1.6m, as compared to 7% (14% of German men) for Germany. Somehow Ukraine retained its sense of national identity, and Germany retained its sense of Germanness.
Rumsfeld came up with the nonsensical line about more soldiers in Afghanistan meaning more targets because Bush had decided to experiment with the idea that a light special ops footprint would be sufficient to pacify Afghanistan. In reality, more soldiers means fewer casualties and more victories. Despite having vastly superior firepower due to the scale of American economic mobilization (40% of GDP), Uncle Sam also made sure he mobilized just about every single able-bodied man he could. Out of a male population of 60m, 16m men were drafted. The Ukrainian equivalent would be 5m men.
That scale is why at Iwo Jima, the Japanese were outnumbered almost 6 to 1, and at Okinawa, the enemy was again outnumbered 5 to 1. That lopsided ratio is why several Japanese soldiers died for every GI lost in battle. Personnel numbers matter a great deal in war, both for winning and keeping friendly casualties down.
Have to look at the demographics. I don't think Ukraine is able to mobilize 5m men. Age limit is up to 45. After that, you're too old to fight.
Japan had plenty of men, but they were in the wrong spot (on the Asian mainland). When Japan surrendered, they still had millions of troops occupying parts of Asia.
Germany faced the same dilemma late in WWI; they had over a million troops in Russia (which had already surrendered) but didn’t dare to bring them westward because they were radicalized after fraternizing with Russians. They were running out of food and ammo, but not men - just reliable men.