Why South America fragments, and what the OAS, TIAR, MERCOSUR and CELAC can (and cannot) do
12.1 The core point
In the January 2026 scenario we have been analysing (a sudden rupture in Caracas followed by contested authority and external involvement), the regional outcome is shaped less by slogans (“sovereignty” versus “democracy”) and more by institutional constraints and divergent national incentives. South America does not respond as a single bloc because its principal diplomatic instruments pull in different directions, and because key states calculate costs through trade, migration, and domestic politics rather than ideology alone. (cidh.oas.org)
12.2 Two competing legal–normative frames in the hemisphere
A. Non-intervention and sovereign equality (strong norm; weak enforcement)
The OAS Charter articulates a robust non-intervention principle (prohibiting armed force and “any other form of interference”). (cidh.oas.org)
Brazil’s own constitutional foreign-policy principles explicitly include non-intervention and peaceful settlement of conflicts, which helps explain why Brasília often defaults to restraint even when it disapproves of a neighbour’s internal politics. (constituteproject.org)
B. Collective defence of democracy (strong language; politically contingent application)
The Inter-American Democratic Charter asserts that peoples have a right to democracy and governments an obligation to promote and defend it, providing a formal basis for collective diplomatic action when democratic order is at risk. (oas.org)
In practice, however, using democracy instruments requires sustained coalition management inside the OAS, where member-state votes determine outcomes.
Implication: In a Venezuela-type rupture, states can legitimately argue either frame; “unity” depends on whether a coalition can convert a normative claim into votes and follow-through.
12.3 The regional toolbox: what each institution really offers
12.3.1 OAS (Organisation of American States): recognition, diplomatic pressure, and democratic instruments
The OAS is the hemisphere’s principal political forum for legitimacy claims. Its record includes formal votes that deny recognition to contested Venezuelan political moves (for example, the OAS Permanent Council’s 10 January 2019 resolution “not [to] recognize” Maduro’s new term). (oas.org)
The Inter-American Democratic Charter is the doctrinal backbone for such moves, but the OAS remains vote-driven rather than “rule-enforced”. (oas.org)
What it can do in a rupture scenario
- Create a recognition narrative (which then shapes access to multilateral financing and diplomatic legitimacy).
- Provide election observation mandates and diplomatic mediation pathways, where states agree.
What it cannot do
- Force compliance inside the target state without member-state commitment and capacity.
12.3.2 TIAR / Rio Treaty: a collective security instrument with a contested modern role
The Inter-American Treaty of Reciprocal Assistance (Rio Treaty/TIAR) is a collective security treaty: an armed attack on one is treated as an attack on all, and it also contemplates responses to other situations that endanger hemispheric peace. (Avalon Project)
Its contemporary legitimacy is debated and its operational use is rare; analytical work notes how infrequently it has been invoked since the Cold War, including attention to the 2019 Venezuela episode. (Stimson Center)
Why TIAR does not unify South America
- Many states view TIAR activation as a pathway to coercion, which collides with non-intervention commitments and domestic political sensitivities. (cidh.oas.org)
- Even where invoked, TIAR’s practical effects depend on participating states’ willingness to escalate.
12.3.3 MERCOSUR: the “democratic clause” with real membership consequences
MERCOSUR’s Ushuaia Protocol anchors democratic conditionality; Venezuela was suspended from MERCOSUR in August 2017 explicitly under that democratic commitment framework. (cancilleria.gob.ar)
What this means in a rupture scenario
- MERCOSUR can impose membership-status consequences (suspension, isolation within the bloc) more credibly than many other forums because it is tied to economic integration and legal membership rights.
What it does not solve
- It does not, by itself, change coercive control within the target state.
12.3.4 CELAC: sovereignty-first regionalism and resistance to unilateral coercion
CELAC often functions as a counterweight to Washington-centred hemispheric politics, with recurring emphasis on sovereignty and opposition to unilateral coercive measures in multilateral statements. (United Nations)
In practice, CELAC tends to generate consensual statements rather than enforcement.
12.4 Why major states diverge: the Brazil–Argentina polarity, and the “migration calculus”
Brazil: “sovereignty + caution” is structurally embedded
Brazil’s constitutional principles explicitly include non-intervention and peaceful dispute resolution. (constituteproject.org)
This does not require approving of a neighbour’s governance; it means Brazil is institutionally predisposed to oppose external imposition and to prefer negotiated regional or multilateral processes.
Argentina: alignment incentives can run the other way
Argentina under Milei has signalled unusually explicit alignment with Washington in public diplomacy and economic positioning, with reporting repeatedly framing Milei as ideologically and personally close to Trump-era politics. (Reuters)
This does not automatically translate into uniform regional leadership—but it increases the probability of pro-U.S. coordination in a rupture scenario.
Colombia, Chile, Peru and others: the refugee–migrant externality matters
The Venezuelan displacement crisis is one of the largest in recent regional history. The R4V platform consolidates host-government figures on Venezuelan refugees and migrants, and UNHCR documentation reports large-scale displacement and ongoing humanitarian needs. (r4v.info)
Colombia in particular has hosted the largest share, with reporting citing more than 2.8 million Venezuelans in-country as of mid-2024. (AP News)
Political consequence: states most exposed to migration pressures may prefer any pathway that plausibly stabilises Venezuela (even if they dislike the legal optics), while still hedging publicly via sovereignty language.
12.5 Why South America does not form an “Asian-style wall”
Four structural reasons dominate:
- No single shared external enemy
East Asian alignment is often anchored by a common perception of China’s coercive rise. In South America, perceptions of the U.S. range from “partner” to “historical intervener”, and Venezuela itself is politically polarising. - Institutional pluralism produces forum-shopping
States can choose OAS (democracy/recognition), CELAC (sovereignty/anti-coercion), MERCOSUR (democratic clause + trade bloc discipline), or ad hoc coalitions. That plurality enables fragmentation rather than unity. (oas.org) - Economic exposure points in opposite directions
Even governments rhetorically critical of Washington often rely on U.S. market access, finance, and security cooperation—while simultaneously depending on China as a commodity buyer. This makes “collective defiance” economically costly. - The TIAR constraint
The existence of TIAR as a latent escalation mechanism tends to polarise rather than unify, because states disagree on whether it is legitimate or dangerous. (Avalon Project)
12.6 What “regional stabilisation” would look like (if fragmentation is managed)
A plausible stabilisation package would have to combine three layers:
- Legitimacy coordination (OAS-centred)
A minimum coalition would need to align around a recognition and sequencing pathway (e.g., transitional authority → electoral timetable → observation mission mandate). (oas.org) - Economic and humanitarian shock absorbers (R4V/UNHCR + bilateral support)
Given the scale of displacement, regional states would need renewed resourcing for host-country services and legal pathways, not merely border enforcement. (UNHCR) - A ceiling on escalation (TIAR containment by diplomacy)
Even if TIAR is referenced, stabilisation requires preventing institutional moves that trigger counter-coalitions and turn Venezuela into a theatre of hemispheric brinkmanship. (Stimson Center)
12.7 Transition to Episode 13
Episode 13 turns to the external actor most structurally disadvantaged in the Western Hemisphere but still economically consequential: China’s adaptation toolkit (security packages, surveillance exports, contracting, and the limits of “ownership” without local coercive leverage).
References
Brazil (1988, rev. 2017) Constitution of the Federative Republic of Brazil (Art. 4). (constituteproject.org)
MERCOSUR (2025) Founding texts: Protocol of Ushuaia (democratic commitment). (mercosur.int)
Ministry of Foreign Affairs of Argentina (2017) ‘Decision regarding the suspension of Venezuela from MERCOSUR through the Ushuaia Protocol’, 5 August. (cancilleria.gob.ar)
OAS (2001) Inter-American Democratic Charter, 11 September. (oas.org)
OAS (1947) Inter-American Treaty of Reciprocal Assistance (Rio Treaty/TIAR). (oas.org)
OAS (n.d.) Charter of the Organization of American States (non-intervention provisions). (cidh.oas.org)
OAS (2019) ‘Permanent Council agrees “to not recognize the legitimacy” of Maduro’s new term’, press release, 10 January. (oas.org)
Stimson Center (2025) ‘The Quiet Demise of the Rio Treaty’, 1 August. (Stimson Center)
UNHCR (2025) Venezuela Situation Summary (Global Report 2024). (UNHCR)
R4V (n.d.) Refugees and Migrants from Venezuela (host-government reported figures). (r4v.info)
Associated Press (2024) ‘Venezuelan migrants keep arriving in Colombia…’, 3 December. (AP News)
Reuters (2024) ‘Argentina’s Milei plays Trump stand-in at G20 summit in Rio’, 19 November. (Reuters)
Reuters (2025) ‘Trump says Milei had “a lot of help” from US for Argentina election win’, 27 October. (Reuters)