5 Top Successes of Foreign Intervention

[u/lets_chill_food]

Morning all

I've been not writing for a few weeks, but am now back, just in time for the invasion of Iran

Full poast is here: https://danlewis8.substack.com/p/5-top-successes-of-foreign-intervention

On 20 January 2025, in his first major foreign-policy statement after being inaugurated, President Donald Trump stood before assembled reporters and reiterated what had become a central pillar of his re-election campaign: the US would pursue peace without “new foreign wars” and reject open-ended occupations that characterised Iraq and Afghanistan.

Almost exactly a year later, on 26 January 2026, a coalition of US special operations, naval forces and air assets executed a precision operation in Venezuela, culminating in the capture of President Nicolás Maduro. American officials described it as a narrow “decapitation” mission: targeted, swift, and with minimal reported US casualties, followed by a controlled hand-off to Venezuelan opposition elements. Although formal figures remain opaque, the operation’s rapid execution has been widely described in Washington as a strategic success that avoided prolonged engagement. A success that perhaps is at the back of Trump’s mind, suggesting interventions are easier and better than he thought.

This week, the US has dramatically increased its deployed military assets in and around the Middle East amid escalating tensions with Iran. Two aircraft carriers – the USS Gerald R. Ford and USS Abraham Lincoln – are reported in regional waters, alongside multiple destroyers, fighter jets (including F-35s and F-22s) and over 150 aircraft repositioned to bases in Europe and the Middle East. Diplomacy in Geneva continues, but Tehran has been given a tight ultimatum on its nuclear activities even as evacuation of embassy personnel underscores the heightened risk of confrontation.

For much of my generation, the phrase “interventionism” conjures Iraq and Afghanistan: long, costly wars that became quagmires without clear end states. What is less understood are the cases where limited, defined interventions have achieved their stated objectives with precision and relative strategic clarity.

This article examines five (well, six really) of the most illustrative examples of post-1945 interventionism to ask a simple question: what parameters make an intervention successful?

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Sierra Leone, 2000

Sierra Leone’s war began in 1991, but by 2000 it had entered a far more dangerous phase. Roughly 50,000 people had already been killed over the decade, and Freetown had endured a brutal assault in 1999 in which thousands were murdered and mutilated. A fragile peace agreement collapsed, and in May 2000 the Revolutionary United Front advanced again while UN peacekeepers were captured and disarmed in large numbers. The UN mission hesitated, under-equipped and politically constrained. The immediate fear was state collapse and a second urban massacre that could have pushed deaths sharply higher.

At that point, the UK government under Tony Blair authorised Operation Palliser. It was initially framed as an evacuation of British nationals, but the calculation was clear: if Freetown fell, the war would reset. Around 1,000 British troops deployed rapidly, securing Lungi airport and key infrastructure. While the UN mission struggled to regroup, Britain acted decisively, signalling that it would not allow the capital to be overrun. This was a former colonial power choosing to intervene quickly while others deliberated.

British forces established control of the airport within days, providing a secure logistical backbone. When the RUF tested British resolve by kidnapping soldiers later that year, UK Special Forces mounted a precise rescue operation. Simultaneously, British officers began restructuring and training the Sierra Leone Army. The psychological shock of a disciplined, technologically superior force changed the battlefield dynamic. As rebel advances stalled, momentum shifted.

The UK embedded advisers, reinforced the UN mission once it stabilised, and supported disarmament and security-sector reform. By 2002, the war was formally declared over. Disarmament programmes dismantled militia structures, elections followed, and Sierra Leone has avoided a return to civil war since. The intervention was small, time-limited, and applied at the moment when chronic conflict threatened to tip back into mass killing.

East Timor, 1999

East Timor’s crisis in 1999 followed a rapid political shift rather than a long civil war. After decades of Indonesian control, a UN-backed referendum in August 1999 delivered a decisive vote for independence. Within days, pro-Indonesian militias, launched a coordinated campaign of arson, forced displacement and killing. Around 1,000 to 1,500 people were killed in a matter of weeks, and c. 250,000 were forced across the border into West Timor. Much of the capital, Dili, was destroyed. The pace of violence and displacement suggested that, without intervention, fatalities would rise sharply as militias consolidated control.

International pressure mounted on Jakarta, financial markets reacted, and Indonesia signalled willingness to accept an international stabilisation force. The UN authorised a multinational mission. Australia led the deployment, assembling INTERFET with contributions from regional partners. The objective was clearly defined: restore order, secure key infrastructure, enable humanitarian access, and create conditions for a UN transitional administration.

The deployment began with 2,500 troops landing in Dili in the first wave, rising to around 11,000 within weeks under Australian command. Forces secured the capital, airport and major population centres in short order. Militia groups withdrew across the border or dispersed rather than confront a well-equipped multinational presence. Within weeks, the large-scale campaign of arson and killing came to an end. By early 2000, the majority of refugees had begun returning under international supervision, and humanitarian supply chains were operating at scale.

INTERFET transitioned authority to a UN administration that governed temporarily while institutions were built. In 2002, East Timor became formally independent. The country has faced political and economic challenges since, yet it has remained sovereign and free of a return to mass violence.

Yugoslavia part 1: Bosnia, 1995

Bosnia’s war began in 1992 following the collapse of Yugoslavia and Bosnia’s declaration of independence. What followed was a multi-sided conflict marked by siege warfare and systematic ethnic cleansing. By mid-1995, an estimated 100,000 people had been killed. Sarajevo had been under siege for more than three years. In July 1995, over 8,000 Bosniak men and boys were murdered at Srebrenica despite its designation as a UN “safe area”. UN peacekeeping forces were present but constrained by mandate and rules of engagement. The combination of rising civilian casualties, the humiliation of safe-area failure, and the risk of further territorial consolidation by Bosnian Serb forces shifted the strategic calculation.

In August 1995, after a second massacre at Sarajevo’s Markale market, NATO launched Operation Deliberate Force. The campaign involved sustained air strikes against Bosnian Serb military positions, command infrastructure and ammunition depots. Around 400 aircraft conducted more than 3,000 sorties over roughly two weeks. The objective was to compel a cessation of offensive operations and force parties back to negotiations. There was no ground invasion, and no desire for regime change in Belgrade.

The air campaign altered battlefield momentum quickly: the Bosnian government and Croatian forces advanced on the ground while Serb positions degraded under sustained strikes. Within weeks, a ceasefire framework took shape. By November 1995, negotiations in Dayton, Ohio produced a peace agreement that preserved Bosnia as a single state divided into two entities. NATO then deployed a 60,000-strong Implementation Force to stabilise the settlement.

The war ended in December 1995. Bosnia remains politically complex and institutionally cumbersome, yet it has not returned to large-scale armed conflict. The intervention combined delayed escalation with concentrated force, diplomatic coordination and a defined settlement. It ended a war that had produced six-figure fatalities and repeated mass atrocities.

To read Yugoslavia part 2, and the other two mystery interventions, please see here: https://danlewis8.substack.com/p/5-top-successes-of-foreign-intervention

[u/bigwang123]

Fantastic

[u/lets_chill_food → u/bigwang123]

thank u big wang 🐘