The government is playing down an opinion poll that shows voters strongly back Australia’s involvement in air strikes in Iraq to help combat Islamic State extremists.

The Galaxy poll conducted for News Corp Australia found 62 per cent of people support Australian air strikes in Iraq and 75 per cent believe the threat of a terrorism attack on home soil is real.

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Defence Minister David Johnston said while he was encouraged by the result, the decision to send in troops was not based on public opinion.

“It’s not a matter of me being encouraged or happy,” he told ABC on Sunday.

“We’ve seen enough to establish in our own minds as a nation pretty well that this situation in Iraq cannot continue.”

Federal cabinet last week approved Super Hornets to start bombing raids against IS extremists in coming days, supported by 400 RAAF personnel.

Australia’s involvement in Iraq has bipartisan support and Mr Johnston said the public was impressed it had not become a political issue.

Labor frontbencher Andrew Leigh – a self-confessed poll sceptic – said there were more important issues than opinion polls to focus on.

“Australians should have confidence in our security agencies in managing the threat and the good wishes of all Australians should go with our personnel serving in the Middle East on our behalf,” he told reporters in Canberra.

Six RAAF F/A18 Super Hornets, an E-7A Wedgetail surveillance aircraft and a KC-30A multi-role tanker transport, as well as 200 special forces troops have been deployed to the Middle East to help fight the IS group.