England may have been rocked by defeat to the Aussies in the tournament’s group stage, but their overall record stands at nine wins from their last 11 games against Aaron Finch’s men.
At one stage after that loss, England’s place in the final four looked in jeopardy before back-to-back wins over India and New Zealand set up the semi-final against the Aussies.
And batsman Root said: “These guys and this group over the last four years, their experience against Australia have been very positive and they have got a lot of success in the bank.
“I don’t see that as a big worry for this group, we will be drawing on that confidence that over a long period of time now we have been successful against Australia.
“I feel we are in a good place coming into it, I feel like the last two days have almost been like knockout cricket for us.
“We have been playing in a high-pressure environment for a while now and hopefully that will hold us in good stead going into this game.
“If we play in the manner we have the last two games, we will be a very difficult side to play against.
“You can look at form, statistically who is stronger, but it all comes down to who handles the day better, who plays the stronger cricket for the longest period and who will stand up and be victorious at the end of it.”
Captain Eoin Morgan, meanwhile, wants his England side to embrace the fact they are "living the dream" ahead of the semi-final.
Occasions do not come much bigger for England cricketers - though a Lord's final on Sunday would fit the bill should they win at Edgbaston - and Morgan fully appreciates the scale of the opportunity.
"Sometimes I'm guilty of it, you can lose sight of the position you're in and the fact you're living your dream," he said.
"I think it's possible to play with a smile on your face."Asked if his side were feeling excited, nervous or simply focused on the task at hand, he said: "All of those things. But I think excitement probably should be the dominant one.
"Everyone is excited to play this semi-final. The fact that through the group stages getting to this stage looked unlikely, or was called into question, makes it even more exciting for us."