The Cardinal was speaking after a two day visit to Erbil in the Kurdish region of Iraq where around 125,000 mainly Christians have fled to from their home city of Mosel and surrounding valleys, after IS swept through villages in August, telling believers to leave, convert or die.
The Cardinal spent two days meeting victims of the violence who are now being housed in Christian-run centres across Irbil.
In an interview with Premier, Cardinal Nicholls said: "This destructive faced has to be repelled and it won't be done with talk", in comments echoing sentiment from the Vatican and Pope Francis.
The Pentagon said on Tuesday that Islamic State (IS) has lost more than a quarter of its territory in Iraq since the US-led coalition air campaign began in August.
The Archbishop of Westminster, who met with IDPs (Internally Displaced Persons), also spoke of the deep conviction believers maintained in their faith, despite being confroned with IS brutality: "I spoke with two 80 year old women - Gazela and Victoria, and they were held by ISIS men for a couple of days and they were trying to convince them they had to convert," he said speaking to Premier's Hannah Tooley.
"They said 'no, kill us - we're not going to give up our faith, and you people are all wrong.' So I think they had quite vigorous conversations these two 80-year-old small, diminutive women dress in black, as tough as boots.
"Now there's no question - none of them would say, for the sake of a building would I give up my faith - they left.
They go, and they go with broken hearts, but they go and they bring the love of their family and their faith in Jesus with them."
Listen to Premier's Hannah Tooley interview Cardinal Vincent Nichols here: