Holey alliance: NATO’s worries at 75

It was formed to unite the world’s strongest countries and preserve peace, but as NATO holds a celebration summit for its 75th anniversary, it faces tricky challenges. Climate change is jeopardising Scottish salmon, one of Britain’s biggest food exports (10:15). And why North Korea is sending hot air balloons over to the South, filled with rubbish and faeces (16:50).

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