It was Ronald Reagan who famously said “there will be no negotiation with terrorists”. Of course, history shows the former US president did precisely that to secure the release of American hostages in the Iran-Contra affair, but his one-liner lives on as a kind of foreign policy mantra, spouted by leaders the world over.

The logic is simple — negotiating with terrorists affords them legitimacy, and democracies must never give in to violence.

But what if the terrorist threat is in your own backyard, carried out overwhelmingly by — and against — your own citizens? And what if decades of other strategies have either failed or brought only limited success? Are there circumstances in which talking to terrorists is the right thing to do?

In Colombia, President Juan Manuel Santos is staking his legacy on achieving a negotiated end to the country’s deadly internal struggle.

And US President Barack Obama, for one, “welcomes President Santos’s deep commitment to working for peace”.

For almost half a century, Colombia has been locked in a bitter and bloody civil conflict, the longest-running insurrection in Latin America. The government estimates the fighting has claimed 600,000 lives, while the United Nations points to 3.6 million internally displaced people. Many Colombians know no other reality.

The two chief protagonists — and there are more — are the Colombian state and the Marxist guerrilla militia FARC (Fuerzas Armadas Revolucionarias de Colombia, or Revolutionary Armed Forces of Colombia). FARC — which is listed as a terrorist organisation by the US State Department, the European Union and others — took up arms in 1964, with the professed aim to seize government and help the rural poor through a redistribution of wealth.

The FARC is financed primarily through kidnapping and drug money, and, at its peak, boasted as many as 18,000 fighters. Its ranks have thinned to about half over the past decade, thanks to sustained operations by security forces that have wiped out much of its top brass and convinced others to defect.

In short, the rebels are reeling. The US-backed strategy of all-out military assault implemented by former president Álvaro Uribe has been as popular as it has been effective. From 2006 to 2009, the double-act of Uribe and his star defence minister — Santos — not only forced the FARC back deep into its jungle hideouts, but orchestrated the bloodless rescue of high-profile hostages, most notably the former presidential candidate Ingrid Betancourt in 2008.

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Ingrid Betancourt, who was rescued from FARC rebels in 2008.

The government has also made significant military gains against the smaller left-wing guerrilla group, the ELN, and Uribe offered demobilisation incentives to various right-wing paramilitary groups that had joined the conflict to protect various local interests by fighting the FARC and the ELN.

By the end of his second consecutive mandate — the maximum permitted under Colombian law — in 2010, Uribe had hand-picked Santos as his successor, confident he would continue his legacy. He was wrong.

Santos quickly infuriated his former boss by signalling that this government would be open to dialogue with the rebels. The military operations have continued, even increased, but gone is Uribe’s “terrorist threat” language, replaced by the softer “armed internal conflict”.

And now, in a potentially career-defining gamble, Santos says the time is ripe to negotiate an end to the conflict.

So, what is driving Santos? Why go to the negotiating table with the FARC seemingly on its knees?

In an interview with Al Jazeera, Santos said: “I think the time is right. They have been trying to get their objectives for 50 years through violence. I think they have realised that this is not the way and I am offering another alternative.”

While this is clearly true, it’s also important to remember this is a man responsible, perhaps more than anyone else, for weakening the FARC. A man who knows the conflict from the inside. With this in mind, his willingness to negotiate looks like a tacit acknowledgment that, for all the heavy blows the government has landed, there is no final military solution to the conflict.

Joshua Mitrotti, the ex-manager of ACR, Colombia’s agency for reintegrating armed militants into civil society, tells The Global Mail he thinks this is the case. “I think [Santos] realises that the war in Colombia cannot end militarily, that this process is necessary to build a peaceful country.

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A FARC guerrilla fires at government forces in El Palo, Colombia, April 2011. Years of sustained, US-backed military assault have left the leftist militia reeling.

“And the FARC could become a very important political player in Colombia. They are not likely to effect any great change at the negotiating table, but later on they could effect change democratically.”

Both sides agreed on a five-point agenda in earlier secret meetings; the process began in earnest on October 18, half a world away, in the Norwegian capital of Oslo. Negotiators sat down to talk through a roadmap to peace. It’s a path Colombia has started down three times before, each an unmitigated failure.

This time, both sides say it’s for real. Chief FARC negotiator Iván Márquez says the rebel contingent comes to the table not with “grudges nor arrogance” but rather “an olive branch”. His opposite, Humberto de la Calle, says the government acknowledges “unjust social differences” and wants to “embark on a road to social change”. The seven-hour talks were largely symbolic but further, more substantive negotiations are scheduled to take place in Havana, Cuba, on Thursday.

Uribe, of course, is livid, branding the process a “slap in the face of democracy” and using Twitter to launch acerbic volleys in the direction of his former colleague. “That’s his problem,” Santos replies, single-mindedly. But the truth is the political stakes are very high. The hawks, led by Uribe, are already circling, waiting for the process to fail. In July, the ex-president announced the formation of a new political movement, Puro Centro Democratico (Pure Democratic Centre), that he hopes will return the country to “Uribism” in the 2014 presidential elections.

Meanwhile, even in its weakened state, the FARC continues to launch deadly surprise attacks from its jungle retreats. Just a day after the Oslo talks, a rebel ambush killed five soldiers.

Santos has ramped up military operations, emphatically rejecting calls for a ceasefire during the process. There will be no concessions at all until a final agreement is reached, he stresses. Santos hopes that by acting now, in the wake of recent military successes, the government will be assured the upper hand in negotiations.

Notwithstanding the government’s bargaining strength, the process will be anything but straightforward. Certainly, the FARC has never been further from its aim of forming a government and could scarcely have less support from a war-weary public. But it is awash in drug money that it will not relinquish lightly. Fundamentally, Santos is betting that he can negotiate peace, and that a peaceful end will justify the means of obtaining it.

The five issues on the agenda signed by both parties are: land reform, ending the armed conflict, cutting the production of illegal drugs, the post-conflict future of the rebels, and justice and reparations. There are some enormous questions lying dormant in there: Will crimes committed during the conflict be punished? Or will amnesties be granted? Will the way be cleared for the FARC to participate as a legitimate political player in democracy?

It’s hard to imagine all of these issues will be thrashed out in negotiations, but perhaps, with the requisite goodwill, negotiators might agree on a ceasefire and establish a mechanism to tackle the bigger stumbling blocks in the democratic sphere. Only then could the price of this peace begin to be measured.

If the FARC’s demand that none of its members face prison time is met, that price could include legions of killers walking the streets with impunity. Some of them might even run for public office. Would this be acceptable to the families of those captured, tortured or killed by the guerrillas? Such questions are always fraught; last year Israel released 1027 Palestinian prisoners it considered terrorists, in exchange for one soldier held by Hamas. Many of these prisoners had been charged with manslaughter, attempted murder or intentionally causing death. The Spanish government is refusing to talk with the Basque separatist movement ETA — which, incidentally, has close links with the FARC — over its imprisoned members. Despite renouncing violence a year ago, ETA is still considered a terrorist organisation by the US and the European Union.

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Thousands of Colombians protest against the FARC militia, December 2011. Peace negotiations have raised hopes that Latin America's longest-running insurgency may be reaching its end.

Colombia’s internal conflict is unique in that there are myriad parties involved — left-wing guerrillas, right-wing paramilitaries (which have been encouraged by business leaders and even, at times, the state), and government armed forces — all guilty of atrocities. Colombian soldiers are being investigated in more than 3,000 so-called “false positive” cases — in which civilians were murdered and their bodies passed off as FARC and ELN battle casualties, by army officers seeking benefits based on rebel body counts.

Colombia’s is a complicated mess and there are dirty hands wherever you look. The ELN has resisted overtures to join this process and neo-paramilitary groups are not involved either. As such, a peace deal with the FARC will not guarantee a broader peace. Nor will it stop the drug trade, but after 50 years of fighting, the symbolic value of a peace agreement would be enormous and it would certainly encourage the ELN to seek a deal of its own. Without leftist rebels to fight, right-wing paramilitaries would be relegated to little more than drug-running organisations.

If talks fail, Santos will be vilified for undermining a decade of military gains in an ill-advised dialogue with terrorists. But according to opinion polls, the majority of Colombians support the talks, though they are divided over the transitional issues (amnesties, the FARC entering politics). Santos is keeping up the military fight in the meantime, and, if the peace process fails, military operations will continue unabated.

The political stakes may be high for Santos personally, but for Colombia there is a lot more to gain than to lose.