The prosecuting barrister in Lisa Smith's trial claims she "enveloped herself in the black flag" of ISIS when she travelled to Syria in 2015.
The former Irish soldier is on trial accused of being a member of the terrorist organisation and of attempting to finance terrorism.
The non-jury Special Criminal Court was told she converted to Islam before she left the army in 2011.
It is the State’s case that by answering a religious call to migrate to ISIS controlled territory in Syria, Ms Smith pledged her allegiance to the group.
The 39-year-old, who’s from Dundalk, Co Louth, denies both charges.
