Curtains opened on UN security council for first time since attack on Che Guevara

Germany has literally brought daylight to UN security council proceedings by opening the curtains in the famous chamber for the first time since a bazooka attack on Che Guevara more than half a century ago.

The German UN mission celebrated its month-long presidency with the symbolic step of calling for the heavy drapes covering the two-storey high windows to be pulled aside to let the sunshine of a New York spring day flood into the council chamber and on to its famous horseshoe-shaped table.

The mission’s Twitter account pressed home the point, declaring: “Transparency & openness to broader @UN membership & civil society are crucial not just symbolically, but also in practice for credibility & legitimacy.”

The gesture also threw light on a forgotten but dramatic episode in UN history. The curtains had been closed after an incident in 1964 when a bazooka was fired across New York’s East River, aimed at the UN building, where Guevara was speaking.

The shell fell 200 yards short of its target, exploding in the river and sending up a high plume of water and rattling the windows of the UN headquarters.

Related: Che Guevara's legacy still contentious 50 years after his death in Bolivia

According to a New York Times account at the time, Guevara, then a major and Cuba’s industry minister, did not pause in his delivery of an anti-American tirade. Later, strolling through the delegates’ lounge in olive-green uniform and polished black boots, the former guerilla was insouciant. With a “languid wave of his cigar” he declared that the blast had “given the whole thing more flavour”.

The bazooka was found in weeds on the far bank of the river, with an automatic trigger mechanism attached to a timer.

According to scprocedure.org, a website devoted to security council goings on, “a later investigation determined that had the bazooka been properly aimed, its shell would have penetrated the UN building, especially if it had struck a window”.

The attack came at the time of angry protests by Cuban exiles outside the UN headquarters.

One of the protestors, a woman called Molly Gonzales, was arrested running towards the building with a hunting knife which she said she wanted to “cut down” the revolutionary leader.

On being told of the identity of his would-be attacker, Guevara remarked: “It is better to be killed by a woman with a knife than by a man with a gun.”

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The drawing of the security council drapes was intended to protect diplomats from flying shards of glass in the event of another attack. And the German decision to open them was made possible in part by a 2013 refurbishment of the chamber, in which shatter-resistant glass was installed.

The open curtains were not the only innovation brought in by the German delegation. The ambassador Christoph Heusgen, arrived to chair his first meeting with an 18 inch hourglass, specially made to help enforce the 5 minute 30 second speaking limit for delegates.

The UK mission hailed what it called an example “German efficiency helping .. speakers get to the point...And we’re very much here for it.”

The British delegation has called for a special council session on Libya on Friday, but – somewhat cutting across the trend towards transparency – asked for it to be held behind closed doors. No word so far on the curtains.