When Kim Il Sung’s troops stormed into Seoul in the early days of the Korean war, scores of South Korean soldiers scrambled atop the advancing Soviet T-34 tanks to detonate explosives and grenades.
Although mostly futile in slowing the North Korean advance, the bravery of those suicide squads — fighting before international support arrived to the peninsula en masse — demonstrated the sacrifices South Koreans were prepared to make to save their country.
Today, after almost seven decades of relative peace under the blanket of US security, military planners in Seoul are again readying for the possibility of defending South Korea alone.
President Moon Jae-in has embarked on military reforms aimed at rapidly improving the armed forces’ technological prowess while simultaneously preparing for far fewer conscripts as the country’s rapidly ageing population declines thanks to low birth rates.
The sweeping changes, according to former military officials and analysts, will have implications across the region.
South Korea is broadening its focus from the singular challenge of deterring attacks from North Korea’s nuclear-armed Kim regime. It is also reducing its long-held dependence on American troops. The shifts tacitly acknowledge the dual threats of waning US commitment and China’s military expansionism. The strategy also reflects the lingering wariness over territorial and historical disputes with Japan.
“What they are trying to do is have a stronger, independent capability that better prepares them for contingencies vis-à-vis North Korea but also potential US abandonment, the rising China threat and increasing suspicion about militarisation in Japan,” said S Paul Choi, principal at Seoul-based political risk advisory StratWays Group.
South Korea’s annual defence bill is already high compared with those of many countries of a similar size and wealth. Military spending as a percentage of government expenditure was 12.7 last year, according to Stockholm Peace Research Institute data, ahead of 9.2 per cent in the US and the UK’s 4.5 per cent.
The defence ministry is set to spend a further Won300tn ($275bn) in 2021-25 — annual increases of about 6 per cent.
Seoul has also unveiled big-ticket armaments, including plans to build a $1.7bn aircraft carrier, enabling South Korea to “proactively respond to threats from all directions”.
The changes follow several years of trepidation in both Washington and Seoul that Donald Trump would make good on threats to reduce the US military footprint in the region, potentially pulling out some of the 28,500 American troops stationed in South Korea.
In Seoul, fears of a sudden US withdrawal have even reignited discussions over whether South Korea should have its own nuclear weapons as a deterrent against Kim Jong Un’s arsenal.
“If North Korea does not co-operate with nuclear talks and keeps its nuclear weapons . . . we have to rethink about arming ourselves with nuclear weapons,” said opposition party leader Kim Chong-in.
Fears of immediate American abandonment have subsided with the election of Joe Biden, who has vowed to strengthen US alliances.
But Mr Trump’s treatment of long-term allies — including demands from the White House that Seoul quintuple its payments for American security — refocused attention on the long-term trajectory of the US-South Korea relationship.
Many experts believe South Korea’s military expansion was inevitable.
“The South Korean people need to be grateful for 70 years of solid support that the United States has provided us,” said Lieutenant General Chun In-Bum, a retired South Korean special forces commander. “But I don’t expect another 70 years of unilateral support. We need to be more independent, just to be a good ally.”
According to General Vincent Brooks, the retired four-star general who led the combined US Forces Korea from 2016-18, the US alliance structure in Asia will have to “change its orientation” to support peace across the Indo-Pacific region in the face of the growing challenge from China.
“This is another dynamic that is happening. I think it is on the horizon, maybe not the next two to three years, but the next 10 to 20 years,” General Brooks said.
But as South Korea reinforces its military capabilities, new problems will emerge, experts warned. The build-up could send unintended signals of aggression or weakness, inviting miscalculations or adventurism from countries including North Korea, China and Russia.
There are also concerns that the South Korean military is developing its technological capabilities before addressing more fundamental flaws.
Lt Gen Chun said that while the increased budget was encouraging, he was “not comfortable” as long as basic shortcomings, including equipment and logistics, remained unaddressed.
“High-tech weapons are no replacement for people,” he said. “South Korean forces need to focus on the basics for the individual soldier . . . I’m talking about a good rifle, a good first aid kit.”
To ensure stability — according to Gen Brooks, Lt Gen Chun and Mr Choi — it will be vital that significant changes in US or South Korean military posture are clearly communicated between the allies, and not one side making a unilateral decision.
“People need to understand that this little piece of land is critical to the balance of north-east Asia,” said Lt Gen Chun. “Before money or anything else we need to talk so that we understand each other.”