'Why are Americans so stupid not to tighten gun laws?' David Koch takes on US gun advocate

Sunrise co-host David Koch has squared off with a US gun lobbyist in the wake of the deadliest mass shooting in the country’s history.

Gun Owners of America executive director emeritus Larry Pratt defended America’s second amendment right to bear arms insisting that “it’s a good thing” and is needed to "restrain" governments, after a retired accountant gunning down 59 people from inside his Las Vegas hotel room.

Koch said Australians were grieving for those killed by Stephen Paddock but questioned how the US could be “so stupid not to tighten gun laws”.

“You are killing each other,” Koch told Pratt.

“You have 25 times more gun related deaths than Australia does… you have a mass shooting on average every day in America.

“The number of people that died in Las Vegas yesterday is more than the total gun related deaths in Australia in a year, apart from self harm."

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Pratt insisted the amendment still had a place in modern society and remained imperative to keep their government at bay.

“The second amendment recognises that the governments are the biggest mass murderers in history and it's designed to restrain the government. It has worked nicely I would say,” Pratt told Sunrise.

“We are the upholder of freedom in the world… we have not experienced tyranny."

Koch questioned Pratt’s “nonsensical arguments”, asking why any American would ever need to own a machine gun or give a gun to their child. He added that the amendment was brought in “when people were using muskets”.

Watch the full Sunrise interview with Larry Pratt here.