Study Shows that the ROK Army Needs at Least 500,000 Troops to Defense Country from a North Korean Attack
An advantage the ROK Army has is that they can count on the US-ROK alliance to bring additional troops and advanced weapon systems to help defend against a North Korean attack:

South Korea must maintain at least 500,000 active-duty troops to defend against potential surprise attacks from North Korea, according to a new military study released Sunday. The report highlights growing concerns over the nation’s shrinking pool of conscripts due to its declining birthrate.
Published in the summer edition of Defense Policy Studies, the study determined the minimum troop requirement by applying the U.S. Army’s minimum planning ratio doctrine to the Korean Peninsula. Under this doctrine, a defending force should be able to hold their position against an attacker with a troop ratio of 1 to 3, whereas an attacker generally requires a ratio of 3 to 1.
The study, led by Kim Jeong-hyuck of the Korea Army Research Center for Future and Jee Hyo-keun of Konyang University, reported that as of 2022, North Korea had approximately 1.28 million troops, compared to South Korea’s 500,000 — representing a roughly 2.6 to 1 ratio. In the Army alone, the margin widened to almost 3 to 1, leaving Seoul’s forces “at the bare minimum for defense,” according to the authors.
You can read more at the link.


But surely they can appeal to Kim Jong-Un’s better nature and avoid war, right?
foolish to think they will receive 100% of requested US forces as if nK attacks it will be in combination with Commie China attacking somewhere else. On top of that, the majority of the reserves they are counting on will be attempting to flee the country.
Required troop ratio myth needs to die. It’s really a question of who can establish and maintain adequate ratio of fire superiority.
@Flyingsword, flee to where? Only so many boats and comercial planes would quickly get grounded. Mass mobalization would not be a problem. Equiping all of them… might be.
The initial invasion of Iraq involed 160,000 coalition troops on offensive against 1.3 million defending Iraqis. Look at how that turned out. Of course the Korean security situation is very different, but the point is that there’s a lot more than just ratios. South Korea’s geography and massive relative economic size gives it major defensive advantages, and those could have been massively amplified by man made obstacles, but they’ve been dismantling those for decades. That’s the real security problem in the short to medium term. That’s not to say declining manpower doesn’t hurt, but North Korea is starting to have that problem too.
An advantage the ROK Army has is that they can count on the US-ROK alliance to bring additional troops and advanced weapon systems to help defend against a North Korean attack:
@GIKorea @setnaffa and the Setnaffarians must be joking.
They voted for Trump — the guy who wants to withdraw USFK from Korea.
Stop whining about Korean defense. You got what you asked for.
If Korea wants lasting peace and security, there’s only one path: go nuclear.
As for @setnaffa @GIKorea and the Setnaffarians — if that’s not what they wanted, maybe they should’ve voted for Kamala.
Flee to anywhere but the battlefield, not to mention most of the labor unions are controlled by nK and will stage massive work stopages paralyzing movement in South Korea.
“They voted for Trump — the guy who wants to withdraw USFK from Korea.”
No he doesn’t.
He wants Korea to pay more.
Withdraw is a negotiating tactic.
USFK is still in Korea and Korea will pay more, as it is cheaper than going alone.
Protip: If your worldview is far from reality, you will never make a good decision.
“labor unions are controlled by nK”
North Korean sympathizers can be liquidated the same way they were in the past. The only thing preventing that is a crisis which a war would certainly provide. Most young South Korean men (a plus 20 margin) are right wing. They’re the ones who make up the bulk of the conscription military. They would likely follow orders.
“will stage massive work stopages”
Automation and decentralized defense logistics has drastically reduced labor requirements. SK maintains large stockpiles of basic munitions. There is buffer to disruptions.
“If Korea wants lasting peace and security, there’s only one path: go nuclear.”
Nukes detere high level warfare (full invasion) but not low level (skirmishes/unconventional war). You still need a strong conventional force. Look at the long running conflict between Pakistan-India-China.
Korea, like everyone else, is moving production to America.
Korea may fall due to an unprepared and unmotivated population, but Korea Inc. will not.
“Hundreds of billions in South Korean investments are being directed toward U.S. industrial facilities in 2025. These moves reflect strategic diplomacy to avoid tariffs and align both countries around manufacturing, tech, energy, shipbuilding, and EV goals. The factories span across automotive, semiconductor, solar energy, cosmetics, pharma, and more.”