Security in New Zealand is already at a high level as troops head to Iraq as part of a joint deployment with Australia, Defence Minister Gerry Brownlee says.
A Cabinet paper has revealed sending troops could make New Zealand a target of Islamic State, but it also says the risk of doing nothing is even greater.
Mr Brownlee said the Government took that advice into account when deciding to send troops to help train the Iraqi army.
He says it was a matter of deciding whether to wait for a threat to materialise in New Zealand before acting, or do something in Iraq.
Mr Brownlee said domestic security agencies were already highly vigilant about the possibility of terrorism.
We don't expect that the threat from the unexpected activity is going to be greater because the troops are there.
"Rather I think we're sending a clear message to ISIS that New Zealand is, like many other countries, not prepared to tolerate the type of random brutality that they seem to be wanting to encourage."
But Mr Brownlee said the difficulty was that it was the unexpected terrorist acts that caused the most problems.