Reforming the UN Security Council
- Matthew Parish
- Sep 27
- 7 min read
The United Nations Security Council, in theory the world's top body in the resolution of international disputes that are causing or threatening violent conflicts around the world, is and always has been in disarray. That is because it is written into the UN Charter that the five so-called "permanent" members have vetoes on any decision made; and when one of those permanent members is the aggressor, or an ally of the aggressor willing to use its veto, then the veto prevents effective resolution of the conflict in question. The insititution is an always been ripe for reform, which has been discussed endlessly but no satisfactory veto-free model has ever been achieved.
Here is a complete, veto-free model for reform of the UN Security Council with minimal moving parts but strong incentives and safeguards. It ties voting and representation to periodically audited measures of economic and military weight, while preventing domination by any single power or region.
1) Council size and composition
25 seats in total.
Three tiers, all without vetoes:
Tier A (10 seats): States with the highest Combined Influence Scores (defined below). Seats are country-specific for the five-year term and reassessed every cycle.
Tier B (10 seats): Allocated by regional party-lists to the next tranche of Combined Influence Scores; seats are state-specific within regions but can rotate among qualifying states after 2.5 years if the region so decides.
Tier C (5 seats): Regional equity seats to guarantee universal voice. One seat per UN regional group (Africa; Asia–Pacific; Eastern Europe; Latin America & Caribbean; Western Europe & Others). These rotate annually within each group, independent of scores.
All members have one seat and a weighted vote (below). No permanent tenure, no veto.
2) The metrics that drive everything
An independent UN Statistical Board (UN-SB) certifies inputs every five years, locking them for the full Council cycle. All inputs use five-year moving averages to damp noise and game-playing.
2.1 Economic Capacity Index (ECI, 0–100)
ECI = 0.7×(GNI-PPP share of world, capped at 20%) +
0.2×(Share of world trade in goods & services, capped at 20%) +
0.1×(Assessed/voluntary UN contributions as % of UN budget, capped at 10%)
Shares are expressed as percentages of the world total and linearly rescaled so that a state with, say, 5% of world GNI-PPP contributes 5 to the first term before weighting.
Caps prevent a handful of very large economies from overwhelming the index.
Using GNI-PPP (rather than nominal GDP) reflects domestic resource capacity available for sustained contributions.
2.2 Military Capability Index (MCI, 0–100)
MCI = 0.5×(Defence outlays share of world, capped at 20%) +
0.2×(Rapidly deployable personnel and enablers, scaled and capped at 20%) +
0.2×(Power-projection assets: strategic airlift, blue-water tonnage, AAR, major ISR; scaled and capped at 20%) +
0.1×(Peace operations contribution: troops, police, enabling units; scaled and capped at 10%)
“Deployable personnel” counts the portion that can be moved and sustained for 90 days.
“Power-projection” uses a basket score (e.g. aircraft equivalents, sealift tonnage, tankers, ISR platforms).
Nuclear status adds no automatic bonus; its effects are captured indirectly through budgets and enablers.
2.3 Combined Influence Score (CIS, 0–100)
CIS = 0.6×ECI + 0.4×MCI
Rationale: economic heft sustains long wars and recovery alike; military capability matters but should not dominate peacetime governance.
3) Seat assignment rules
Rank states by CIS.
Top 10 become Tier A for the cycle.
Next 10 by CIS fill Tier B through regional lists, with each region guaranteed at least one Tier B seat; remaining Tier B seats distributed proportionally to each region’s aggregate CIS.
Tier C: one seat per region rotates annually, independent of scores.
When a state’s CIS rises or falls mid-cycle, nothing changes until the next five-year assignment, preserving stability and predictability.
4) Weighted voting power
Each seated member has a Voting Weight (VW) derived from its locked ECI and MCI:
VW = 0.5×(ECI/World-sum of ECI of seated members) +
0.5×(MCI/World-sum of MCI of seated members)
This yields normalised shares that sum to 1 across the 25 seats.
A single-state cap of 12% prevents outsized dominance; any excess is redistributed pro-rata to others.
A regional floor: each region’s seated members together hold at least 10% of aggregate VW; if a region falls short, its members are lifted pro-rata to 10% and the remainder is trimmed across others proportionally.
A Tier floor ensures Tier C members jointly hold 7.5% of VW to guarantee meaningful influence.
5) How resolutions pass (no vetoes anywhere)
Every resolution class requires concurrent majorities to balance numbers, weight, and geographic breadth. Abstentions count as not in favour.
Class A: Procedural and agenda
Passes with: (i) simple majority of members present and voting and (ii) ≥50% of aggregate VW.
Class B: Sanctions, commissions of inquiry, referrals, arms embargoes
Passes with: (i) ≥60% of members (at least 15 of 25) and (ii) ≥65% of aggregate VW and (iii) support from at least three of five regional groups (counted by majority of that region’s seated votes, weighted or unweighted—region may choose; default unweighted).
Class C: Authorisation of force under Chapter VII, robust peace enforcement mandates, and no-fly or maritime exclusion zones
Passes with: (i) ≥70% of members (at least 18 of 25) and (ii) ≥75% of aggregate VW and (iii) affirmative majorities in all five regional groups; or four of five plus a certified “Mass Atrocity Trigger” finding by the Secretary-General.
Emergency measures under Article 99-bis (see §9) may be tabled on 24 hours’ notice; voting thresholds are unchanged.
6) Minority brake (not a veto)
If ≥35% of members drawn from at least three regions vote No on a Class B or C item, an automatic Cooling-Off Period of up to 72 hours is triggered for consultations and amendments, after which the identical or amended text may be re-voted once. This slows rushed action without conferring blocking power on a single capital or region.
7) Incentives and penalties (score-linked)
Positive: certified in-kind enablers for UN operations (airlift hours, medevac, engineering) add up to +1.0 CIS point per cycle, capped, to reward practical help.
Negative: systematic non-compliance with Security Council decisions or UN sanctions can subtract up to −2.0 CIS points at the next certification, on the recommendation of the UN-SB and approval by a Class A vote.
These nudges change future influence, not votes within the current cycle.
8) Transparency and audit
UN-SB publishes methodology, raw inputs, and country-level ECI/MCI/CIS with uncertainty ranges.
All normalisations, caps, floors and redistributions are shown in a public spreadsheet so states can reproduce the mathematics.
Disputes over input data go to an Evaluation Panel of five statistical agencies seconded from different regions; decisions by simple majority within 30 days.
9) Agenda control and emergency tabling
Any three members from at least two regions may add an item to the agenda (Class A threshold).
The Secretary-General may table an item under a new Article 99-bis with a written risk assessment; this forces an up-or-down Class A vote within 48 hours to add the item.
10) Committees and mandates
Sanctions Committees are chaired by Tier B or C members by default, to avoid concentrated control.
• Mandates carry sunset clauses: 12 months for sanctions; 6 months for force authorisations, renewable by the same class thresholds.
• A Post-Action Review is mandatory within 90 days of any Class C action, chaired by a member in a region not involved in hostilities.
11) Periodic reassessment and transition
Cycle: every five years (e.g., 2026–2030, 2031–2035).
Timeline:
• T-12 months: UN-SB releases provisional ECI/MCI inputs.
• T-9 months: States may contest data; Evaluation Panel rules by T-6.
• T-5 months: Provisional CIS rankings and regional allocations published.
• T-3 months: Final lists and VW weights locked.
• T-0: New Council seated; outgoing completes open business in a two-week overlap.
To ease the shift from the current Charter, the first cycle can include a grandfather clause ensuring any current P5 that falls out of Tier A still receives a Tier B seat in cycle one only, with no special voting privileges.
12) Legal architecture
Amend Articles 23–27 of the Charter to reflect: 25 seats, no veto, tiered seat allocation, weighted voting, and the concurrent-majority thresholds.
Insert new Articles on UN-SB, Evaluation Panel, data transparency, and Article 99-bis emergency tabling.
General Assembly retains “Uniting for Peace”; this framework complements rather than displaces it.
13) Illustrative walk-through (hypothetical numbers)
Suppose the 25 seated members in a given cycle collectively sum to ECI = 1,250 and MCI = 1,000. A given Tier A state with ECI 80 and MCI 70 gets:
ECI share = 80/1,250 = 6.4%
MCI share = 70/1,000 = 7.0%
VW = 0.5×6.4 + 0.5×7.0 = 6.7% (subject to the 12% cap and any regional floor adjustments)
A Class C resolution receives 19 yes votes (≥70%) and 76% of aggregate VW, with affirmative majorities in Africa, Asia–Pacific, Eastern Europe and WEOG but not in GRULAC. It passes because it meets 18/25, ≥75% VW, and 4 of 5 regional groups.
14) Why this works
Power reflects capacity, openly measured, and evolves as the world changes.
No state can block alone; equally, sheer headcount cannot steamroller the materially responsible.
Regions always have a voice; small states can band together to slow, amend, and review.
Incentives reward those who underwrite collective security with resources and enablers.
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What would the UN Security Council look like in 2025, using this formula?
The figures are approximate, based upon the best working data available to the author.
Country | Final approx voting weight |
USA | 12.00 % |
China | 12.00 % |
India | ~5.6 % |
Russia | ~3.1 % |
Germany | ~2.6 % |
Japan | ~2.4 % |
UK | ~2.2 % |
France | ~2.0 % |
Brazil | ~1.7 % |
South Korea | ~1.5 % |
Canada | ~1.8 % |
Australia | ~1.7 % |
Italy | ~1.6 % |
Spain | ~1.5 % |
Saudi Arabia | ~1.3 % |
South Africa | ~1.2 % |
Mexico | ~1.1 % |
Indonesia | ~1.0 % |
Türkiye | ~1.0 % |
Argentina | ~0.9 % |
Nigeria (Tier C) | ~0.8 % |
Vietnam (Tier C) | ~0.8 % |
Ukraine (Tier C) | ~0.8 % |
Colombia (Tier C) | ~0.8 % |
Sweden (Tier C) | ~0.8 % |
Below appears a full draft Treaty amendment to put into force the proposal contained in this essay. It is prepared in English only, although it would have to be written in the six official languages of the United Nations.
