Major new anti-terror laws are being introduced to reduce the threat from foreign fighters coming home radicalised.
Figures show more than three times as many Irish Muslims have been to Syria compared to British Muslims.
One in every 1,500 Irish Muslims have travelled to Syria. In the UK, it is more like one in every 5,000.
Housam Najjar fought alongside Libyan and Syrian rebels and has now returned to Dublin.
He insists he was not radicalised, but says it is easy to be.
Abdel Basset-Elsayed's son was shot dead on the Syrian border, having travelled to the country to help in the humanitarian effort.
He says he brought him up as a moderate Muslim, and does not think he would have been persuaded by the likes of Islamic State.
The Criminal Justice Terrorist Offenses Amendment Bill introduces three new offences: public provocation to commit a terrorist offence, recruitment for terrorism and training for terrorism.
Those found guilty could face up to 10 years in prison.
Foreign Affairs Minister Charlie Flanagan talked about the new laws last month:
