What's driving the current tension?

Helicopters, armored vehicles, anti-aircraft batteries, mobile rocket launchers and troops — last week Venezuelan President Nicolas Maduro launched a military maneuver on the border with Colombia to demonstrate that Venezuela is capable of warding off a possible invasion. Remigio Ceballos, head of the armed forces' High Command, led the first day of the exercises and said that Venezuela "had friends all over the world" — in reference to the presumed presence of Russian and Cuban officers among the 150,000 soldiers.

Then on September 12, the United States invoked the Inter-American Treaty of Reciprocal Assistance (TIAR), also known as the Rio Treaty. Washington said the call to invoke the regional defense pact, which could facilitate a military offensive against the Maduro government, came from the opposition. Venezuelan opposition leader Juan Guaido and the states supporting him have not recognized Maduro's recent election to a second term in office, claiming the vote was manipulated. The Venezuelan government, which withdrew from the TIAR in 2013, describes the opposition's call to enforce the agreement as a "hostile act" against national sovereignty.

The US said the call to invoke the TIAR came from the Venezuelan opposition, which is led by Guaido

How likely is war?

Sabine Kurtenbach, deputy director of the Hamburg-based GIGA Institute for Latin American Studies, sees the TIAR dispute as the source of the current tensions. "The military exercises are Maduro's response to Guaido's call for members of the Organization of American States to apply the TIAR agreement against Maduro," Kurtenbach said, adding that Ivan Duque, the president of Colombia, has accused Maduro of harboring Colombian guerrillas on Venezuelan territory.

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But it is unlikely a war will break out between these two countries, she said. "Neither really wants that — people in Bogota and Caracas are aware it would be a disaster, and no one on the continent is in favor of multilateral military intervention in Venezuela, regardless of whether TIAR is activated or not." In addition, Kurtenbach said, it is impossible to imagine a regional military intervention in Venezuela without the participation of the United States. The White House has just fired its national security adviser, John Bolton — precisely because of his bellicose attitude, she pointed out. "Washington doesn't seem to want to initiate another military adventure."

'War can't be ruled out'

However, Detlef Nolte, Latin American expert from the German Council on Foreign Relations in Berlin, noted that these kinds of conflicts "often develop their own dynamics." That's why, he said, "a war cannot be completely ruled out." Bilateral relations have also become complicated, he added. "At the joint border, Colombian ELN and FARC guerrillas, the Colombian military and the Venezuelan military that is participating in the military exercise are coming pretty close," he said.

Colombian guerillas, as well as the Colombian and Venezuelan armies are operating in close proximity in the border region

Intervention by the US is also conceivable, said Nolte, who believes that Bolton's dismissal is "not so crucial." Should Maduro prevail, the United States would probably carry out selective attacks without intervening on a large scale, he said.

Conflict not 'first choice' in the TIAR

Phil Gunson of the International Crisis Group, a nongovernmental organization dedicated to conflict prevention around the world, agrees that Venezuela's potential re-entry into the TIAR agreement does not necessarily mean its members are willing to overthrow Maduro. "The TIAR agreement does not proclaim military intervention as the first choice for conflict resolution," he said.

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"On the contrary, the agreement demands that all peaceful aspirations be exhausted before resorting to a military option," Gunson said, pointing out that military intervention in Venezuela would require the approval of the UN Security Council. "And that will not happen," he said.

"If both sides listen to reason, there will be no war between Colombia and Venezuela," Nolte said.