They are dangerously wrong! The war was declared by Mohammed, against all "unbelievers", more than 1400-years ago and is perpetual until all such either join Islam or accept the degrading and slave-like status of dhimitude. This war continues throughout the world, to this day, in such places as The Sudan, other parts of Africa, Thailand, The Philippines and the USA.
That war is called Jihad which may be conducted by individuals (eg Major Hasan of Fort Hood treason & infamy), small groups (eg The 19 "martyrs" of "9/11"), State supported bands (The janjaweed of The Sudan) and even national armies.
Islam requires that all of its adult males wage military/violent jihad or "support it with all their wealth" (The end point of much/most "Islamic charities").
Islam itself is NOT a religion; But, a criminal-terrorist movement whose basic teachings allow or encourage the use of murder, rape and enslavement, genocide, the above-noted perpetual war, unjust treatment of women and "unbelievers" with the goal of destroying all forms of government and law other than under Sharia. That Islam is a religion is the biggest lie in history---And, makes a liar of everyone who repeats it.
As a Christian I am not to hate individuals (eg Muslims); But, I do hate Islam and will support all efforts to destroy it and those who wage war or plan to wage war in its name.
Since we are at war with Islam (As declared by Mohammed and continued by his followers to this day), we should make the same efforts we used to destroy Nazism. Any future "9/11" style attack should be answered by an "object lesson"; The only problem is selecting the right target.
For those who beat the drum of forgiving enemies, I am willing to do so (We should be willing to do so) when the sinners admit their offenses with the real intent of not repeating them! ('Go and sin no more".)
Failure to tell the truth about Islam (Or forwarding it in any manner) is "bearing false witness" against the multitude of the victims of that Nazi-like ideology and is evil in itself by any such acts of commission or omission.