In 2019, David Walsh stepped down as chief executive of Netwatch, the Carlow-based security business he had co-founded in 2002. It was a planned exit; he had sold the majority of the company the year before to private equity firm Riverside, a deal that saw the company merge with businesses in Britain and the US to create the Netwatch Group. From its humble origins, where three people used VHS tapes to monitor a commercial warehouse in Carlow, it had grown to 550 staff monitoring 300,000 sites around the world by the time Walsh stepped down. Using satellite, artificial intelligence, and…