The 57-year-old left his family in Glasgow when he was a teenager to move to Israel, where he lived on a kibbutz.
His brother Colin, from Glasgow, says he now “is filled with dread” as a Jew living in Britain.
“Hamas want us off the face of the earth,” said Mr Cowan. “How can we live in this society today knowing that there are terrorist organisations out there who only want to murder and eradicate Jews from the world?”
Recent pro-Palestinian protests, where a minority have carried antisemitic banners and chanted slogans perceived as antisemitic, have left many Jews scared.
Pro-Palestinian protests have taken place across the country
“My nephew, my brother’s son, asked me if I would come and live in Israel because of the antisemitism in the UK,” he said.
“As Jews we are worried. I’m not a fearful person but it does fill me with dread where we are at the moment and where we could end up. Britain was meant to be safe but maybe it’s not.”
He added: “When I walk down the street I’m thinking: ‘What would they do if they knew I was Jewish?’ And that’s a horrendous thought. I ask, are we any different to where Jews were in Germany in 1938?”
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“People have a right to protest as we have freedom of speech in the UK,” he said. “The problem with the protest is there’s that element which isn’t just about the humanitarian side.
“There’s an element within these protests, which is about Hamas and supporting that organisation and that’s where the fear comes.”
The attack on Israel on October 7 sparked a war in Gaza
Mr Cowan says he feels unnerved by the demonstrations and particularly by the use of slogans like “from the river to the sea, Palestine will be free,” referring to the River Jordan and the Mediterranean Sea.
The chant has drawn criticism from some, including ex- Home Secretary Suella Braverman who said it was an “expression of a violent desire to see Israel erased from the world”.
Despite living so far away, Bernard remained close with his family in Scotland and visited regularly.
Mr Cowan said: “We break down thinking: ‘Why is he not here?’ It was recently my birthday and I always got a message from him saying ‘happy 21st.’
“That was Bernard, he was always joking. And it never came this year. So yes, it’s been a tough time.”