Children are seeing through the short-termism of politics and the current generation of politicians, according to former Liberal leader John Hewson.

On ABC’s Q&A program on Monday night, Hewson said the modus operandi of leaders such as US president Donald Trump and Australian prime minister Scott Morrison was to target nervousness about alternative policies and instead focus on short-term political gain.

“The system has become sort of inward looking and self-absorbed. The sort of people who get preselected these days are not necessarily those who will make good ministers,” he said. “The skills you need to get through the factional process to be preselected in any of the major parties are not skills that will help you run a multibillion-dollar portfolio.

“We’re getting the wrong people.”

Hewson singled out, in particular, the “tribalism” of Australian politics leading to inaction on climate change for the past decade, and said the next generation would see through the short-termism.

“That’s where I think the Greta Thunbergs and my kids see what’s wrong with us. They see we’ve missed the point,” he said.

“I know it’s black and white, you’re either doing it or you’re not doing it, but it [will] make a big difference that the next generation as soon as they vote, you’ll have a very different world in this country and I think globally.”

In September Morrison responded to Thunberg’s speech to the UN, saying he wanted Australian children to grow up feeling positive about the future, without any anxiety.

Chloë Spackman, director of programs at Australian Futures Project, said the debate needed to be reframed.

“I think we need to reframe the conversation as it’s urgent and we need to do something but we want to be doing that from a place of possibility,” she said.

Science writer Julian Cribb said people shouldn’t be scaring children, but informing them.

“They can then apply their minds to solving them … Greta Thunberg and the rest are already into that and they will change the world whether we like it or not.”

Veena Sahajwalla, inventor and director at the Centre for Sustainable Materials Research and Technology, said people can be positive about the possibility of innovation in response to the challenges facing the world.

“I think the ability to see that there are positive solutions and to be able to think about how we might be able to convert something that might sound like it’s all doom and gloom but when you unpack it and think about what we can do with new technologies as we’re developing new technologies, I think it’s fantastic,” she said.