@Greatest I am,
I think if you're going to call Islam an ideology, you have to first define ideology. Then, you have to define other religion's ideologies. Like, Christianity and Judaism. Because the term ideology is usually used in reference to political or economic systems, it's harder for me to think of something that could or has formed the basis for Christianity's ideology, though I'm sure plenty of things exist. With Islam and Judaism it's much easier because I know of clear examples that qualify for the definition I've identified. There's Zionism, Israel, the idea of a "chosen people" for Judaism, which all tie into what might be called Judaism's ideology. Obviously, most people know that not all Jews believe in all those things, even though there's scriptural basis for that idea. With Islam, there's a slew of ideas like Sharia law that terrorists have used to justify their violence against nonbelieving people. Same as with Judaism, most people know that not all Muslims believe in these ideas that could nonetheless be called Islam's ideology.
Let's be honest with whom? People have already identified Islamism as a problem that needs to be dealt with. I will concede that perhaps more can and should be done to deal with Islamic terrorism. What I don't understand is some people's need to conflate a clearly destructive belief system with the faith that millions of people practice.
If you didn't get that last part: the faith that millions of people practice.
So, should we declare war against this immoral ideology?
If by ideology you mean the faith that millions of people practice, the answer is obviously no.