Terrorists Khaled Sharrouf and Mohamed Elomar have reportedly been killed fighting for ISIS in the Middle East.

Sharrouf made headlines around the world for posting pictures of his son holding the severed head of a Syrian fighter.

Elomar, who has been fighting in Syria for about two years, was reportedly involved in the executions of captured Iraqi soldiers, pictures of which were also posted on the internet as a recruiting tool.

Their deaths are a stark reminder that some Australian citizens are taking the side of terrorists and willingly joining Islamic State.

The federal government's plans to strip dual nationals of their Australian citizenship is one suggestion that has caused much debate. That debate has extended to Cabinet, which was divided on the matter, and led to extraordinary leaks of the confidential discussions.

It is effectively an extension of the 1948 laws that removed citizenship from dual nationals who fought for other countries at war with Australia.

The argument extends that those involved in terrorist organisations that Australia is helping to fight should be treated as enemy combatants.

If that party has dual citizenship, then they have made their allegiances known by fighting against what Australia stands for.

Taking the citizenship of sole citizenship Australians is a more vexed matter as it threatens to leave people stateless.

However, many Australians, given the choice between allowing terrorists to keep their citizenship or kicking them out, would pick kicking them out.

The proposed laws must make Australia safer and stand up to any legal scrutiny, but they should be widely accepted.