In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Shaikh Saaleh Al-Fawzaan [may Allaah preserve him] said:
Do not side with the people of Fitna, support, assist or defend them- because [that would necessitate] that you have shared in their [actions] if you defend them and consider their views to be correct, even if you did not come out alongside them [physically], then you have [still] shared in their sin, rebellion and transgression. Nowadays there are those who side with the people of Tafjeer and Takhreeb [i.e. those terrorists who detonate bombs to kill innocent civilians and cause destruction] and they call this jihaad in the path of Allah. [Ref 1] They kill Muslims and the Mu’aahideen [i.e. those non-Muslims whose safety is guaranteed by way of a covenant] [Ref 2]. They cause destruction and terrify the Muslims, and they say, or those who support them say, ‘’This is jihaad in the path of Allah’’ and they defend them. These people [i.e. those who support the terrorists] are judged the same as the terrorists and Allaah’s refuge is sought- because they aid them and consider their views to be correct. There is great danger in this affair, because you [i.e. the one who supports terrorists] are considered as one who shares [their sins] even if you did not carry a weapon alongside them- due to the reason that you aid them and consider their views to be correct; rather what is even more serious is that you describe their actions as [acts of] Jihaad in the path of Allaah. [Ref 3]
Ref 1. With Which Intellect and Religion Can Suicide Bombings and Destruction Be Considered Jihaad? See here:
Ref 2: Shaikh Ibn Uthaimeen on Interacting With Non-Muslims in Western Countries
Ref 3: Jihaad In Our Times: