A diplomatic trip is supply-chain geopolitics in disguise. Official briefings frame President Lee Jae Myung’s 11-day, five-country tour as economic diplomacy and Global South engagement. The itinerary tells a different story: San Francisco for AI and venture capital, then three consecutive stops in Brazil, Chile, and Argentina — nations holding rare-earth elements critical to semiconductor manufacturing, lithium essential for electric-vehicle batteries, and shale gas reserves. Every mineral-access agreement on this agenda is a partial rerouting of South Korea’s supply chain away from the country that refines roughly 90 percent of the world’s rare-earth elements and roughly 68 percent of its lithium — China, which the briefing does not mention but whose market position structures every item on the schedule.

Whose account the tour advances

The official account, delivered by National Security Adviser Wi Sung-lac, describes the tour as a vehicle to “expand trade and investment” and “broaden South Korea’s diplomacy in the Global South.” The stated beneficiaries are South Korean companies seeking new markets and the three host governments seeking foreign capital. The actual beneficiaries are South Korea’s semiconductor and electric-vehicle battery sectors, which need reliable access to rare-earth elements (Brazil), lithium (Chile, Argentina), and shale gas (Argentina).

The Silicon Valley venture capital ecosystem also benefits from the San Francisco leg, which Wi said would “connect the South Korean and U.S. venture investment ecosystems” and give South Korean startups access to international funding. The presidential office has framed three national AI and semiconductor projects — with combined corporate and government investment pledges exceeding $600 billion — as the domestic rationale for the trip.

The hosts have their own agendas. Brazil’s President Luiz Inácio Lula da Silva gains a state-visit format that signals prestige: a joint news conference, signed memoranda of understanding, and a state luncheon. Chile’s recently inaugurated President José Antonio Kast — inaugurated March 11, 2026 — secures early high-level engagement and a chance to modernize the 22-year-old free trade agreement with South Korea, the first such agreement Seoul signed (in force since 2004). Argentina’s President Javier Milei lands the first South Korean presidential visit in 22 years — a diplomatic milestone he can frame as evidence of recovering international standing — plus potential investment in the Vaca Muerta shale formation and lithium extraction.

Three parties are absent from the official framing. Bolivia, the third member of South America’s “lithium triangle” besides Chile and Argentina, is not on the itinerary despite holding the world’s largest lithium resources. The briefing names the lithium triangle but does not schedule a stop in La Paz; Seoul has assessed Bolivian lithium as politically inaccessible through this framework, the Bolivian government having historically demanded technology-transfer and state-controlled extraction terms. Environmental and indigenous communities in each host country’s extraction zones are not mentioned, though Chile’s ratification of ILO Convention 169 gives lithium-region communities formal consultation rights that constrain the pace of extraction regardless of presidential-level agreements. China, the dominant player in rare-earth processing and lithium refining, is never named — though every mineral-access deal on the agenda is a step toward reducing South Korea’s reliance on Beijing.

How the sequencing works as leverage

The itinerary’s structure — San Francisco on days 1–2, Brazil on days 3–6, Chile on days 7–8, Argentina on days 8–10, then Frankfurt on day 11 — creates a sequential game with incomplete information. Each bilateral partner does not know the precise terms Lee is discussing with the others, but the public itinerary means each knows that the others are being visited. This competitive pressure, visible in the schedule, gives South Korea negotiating leverage it would not have in an isolated bilateral setting.

Seoul’s diplomatic narrative frames the tour as positive-sum: all parties gain from expanded commerce. The actual strategic logic is zero-sum. The competition for limited offtake agreements means each ton of lithium or rare earth committed to South Korea is unavailable to other buyers, including China. The equilibrium that emerges from backward induction is a hub-and-spoke arrangement in which South Korea, as the hub, captures the largest share of marginal gain because it is the only player with simultaneous alternatives.

Working backward from the trip’s terminal nodes clarifies what each stop is worth. Brazil carries the most consequential potential outcome: memoranda of understanding on rare-earth cooperation with a nation holding major reserves of the elements that underpin semiconductor manufacturing. Chile offers the most concrete deliverable: modernizing a free-trade agreement that has been in force since 2004 — an upgrade to an existing framework both sides have already signaled willingness to modify. Argentina provides the highest symbolic value — the first official South Korean presidential visit in 22 years — but the least predictable substance, given policy unpredictability under the Milei administration. The two-decade gap creates plausible first-mover conditions: the country that re-engages at this level secures a relationship baseline that later entrants compete against, though the advantage depends on the substance of what Lee and Milei sign, not the symbolism of the visit alone.

The U.S. leg is upstream input. The AI summit and venture-capital meetings in Silicon Valley give South Korea’s delegation technology-transfer credibility it can trade in South America. If the San Francisco leg produces only photo-ops, the South American negotiations lose their bargaining chip. If Lee returns with trackable VC commitments, those commitments strengthen his hand when discussing investment partnerships with Lula, Kast, and Milei.

What is credible and what is cheap talk

The trip itself is a credible commitment device: 11 days, a fixed public itinerary, sunk costs. Signed MOUs with Brazil are concrete and trackable. The Chile FTA modernization builds on a 22-year-old agreement both sides have already agreed to modify, making it the most likely deliverable to close during the tour.

Other claims carry less weight. Wi’s statement that the trip will “significantly increase trade with these countries” is a general aspiration with no conditionality, benchmarks, or sunk cost on South Korea’s side. The prospect of restarting Mercosur trade negotiations is cheap talk — it requires consensus among four member states (Brazil, Argentina, Uruguay, Paraguay), and Lee’s bilateral leverage with any single partner is insufficient to force bloc-level action. Language about “broadening diplomacy in the Global South” is diplomatic aspiration without specific forum, mechanism, timeline, or dollar amount.

The strategic recommendations from the game-theory read suggest that to maximize the tour’s value, Seoul should announce Brazil MOU outcomes before the Chile and Argentina stops to increase competitive pressure, pre-announce specific dollar commitments for mineral-processing investment, and establish a standing Korea–South America critical-minerals dialogue that shifts the interaction from one-shot visits into a repeated-game space where cooperation is more stable. Coalition formation with the United States and Japan on a joint critical-minerals investment framework would reduce Seoul’s vulnerability to Chinese price competition.

The stability of the hub-and-spoke arrangement holds as long as Seoul maintains credible parallel engagement with all three hosts — if any partner concludes it is Lee’s only viable option, the competitive pressure collapses — and as long as at least one bilateral deal closes with concrete deliverables during the trip. The arrangement also assumes each South American host behaves as a rational economic actor weighing Korean investment against alternatives. In practice, Lula’s preferences span dimensions that include Global South solidarity and state-led development models; Milei’s policy unpredictability creates a gap between stated openness and actual deal terms; Kast’s recently inaugurated government may prioritize domestic political signals over optimal economic negotiation. Host governments may also exhibit status quo bias toward Chinese investment, because Chinese state-owned enterprises make non-transparent deals and accept lower returns that Seoul’s private-sector model cannot match.

The 11-day duration itself carries risk. If diaspora events in São Paulo and Frankfurt consume time that would otherwise go to bilateral meetings, the compressed schedule undermines the competitive-signaling mechanism that makes the sequencing work.

Branching futures

Two plausible post-trip trajectories define what this tour actually achieves.

Trajectory one: binding commitments shift the equilibrium. The Brazil state visit produces not just MOUs but specific processing-investment terms — a commitment from Lula’s government to allow Korean capital into rare-earth processing, not just mining. The Chile FTA modernization includes lithium-specific provisions that lock in Korean access to Atacama salt-brine projects. Argentina produces concrete offtake terms for Vaca Muerta gas and lithium. Under this trajectory, South Korea’s supply-chain diversification gains real traction, and the competitive pressure built into the itinerary pays off. The branching point is whether Brazil agrees to processing-investment terms during the state visit. The decision-makers are Lula and his mining ministry, who must balance foreign investment against domestic processing ambitions.

Trajectory two: MOUs and no consensus. The Brazil deal stays at the MOU level. The Chile FTA modernization proceeds but without lithium-specific provisions — a general trade upgrade that changes nothing about mineral access. The Mercosur restart stalls because Brazil and Argentina cannot agree on a joint negotiating mandate. Argentina offers warm statements but no binding offtake. Under this trajectory, Lee returns to Seoul with diplomatic gains but no structural shift in supply-chain dependence. China’s position remains unchanged. The branching point is the same — whether Brazil agrees to processing-investment terms — but the outcome splits on whether Lula’s government sees Korean investment as worth the political cost of overriding domestic mining-sector interests.

What the framing leaves out

The most consequential absent party is China. Beijing holds dominant positions in the very supply chains Seoul is trying to diversify, and is already the largest investor in South American mining across all three countries Lee is visiting. The tour’s architecture implicitly creates a fragile coalition against Chinese supply-chain dominance, but the coalition is fragile because the host governments have divergent interests — Lula favors state-led development, Milei favors market liberalization, Kast is between them — and each has domestic constituencies that block extraction.

Bolivia’s exclusion from the itinerary marginalizes its position. A Korea–Chile–Argentina lithium corridor that routes around Bolivian reserves leaves the world’s largest lithium resource-holder outside the framework Seoul is constructing.

Environmental and indigenous communities in extraction zones are not represented in the official agenda. Chile’s Atacama communities have raised water rights and salt-flat preservation concerns; Brazil’s Amazonian communities have land rights and deforestation worries; Argentine provincial constituencies vary in their willingness to host mining operations. Agreements signed at the presidential level face implementation risk from the ground up if these communities are not engaged.

What the trip will reveal

The trip produces binding supply contracts or it does not — and if MOUs are the ceiling, South Korea’s mineral dependence on China remains structurally unchanged. How China responds — with competitive financing offers to South American governments, diplomatic pressure on Seoul, or accelerated purchasing contracts — determines whether the tour’s gains hold. The absence of Bolivia and community stakeholders from the itinerary creates bottlenecks that undo the agreements signed this week, because extraction deals signed without community consent face implementation risk that presidential handshakes cannot resolve.

Analytical techniques used in this piece

This analysis applies the methods below. Each links to a short, plain-English explainer you can read and reuse.

Scenario Planning
Builds a small set of distinct, plausible futures to plan against.
Stakeholder Mapping
Charts the parties to a situation — their interests, power, and alignments.
Strategic Interaction (Game Theory)
Models a situation as a game — players, moves, payoffs, and likely equilibria.