1. My understanding of ideology is that it is the collection of political views that someone holds, whether or not they actually benefit you. Sometimes this correlates with a political party (Republican, Democrat) but sometimes it correlates with a political identity (liberal, socialist, conservative). Sometimes peoples’ collection of beliefs do not fit neatly into any of these categories. An example of this could be someone who leans liberal on most but not all issues — they may be in favor of increasing spending on social programs, cutting the defense budget, and in favor of marriage equality, but strongly oppose abortion.
This being said, ideology is the category of the collection of beliefs, rather than one individual’s specific beliefs. It is another way to identify and align with others within a divided community, and sometimes it is more about principles rather than specific beliefs.
2. In the US, conservative ideology seems to align with concepts like cutting government spending and size, supporting private business rather than public services, and preserving independent autonomy above the collective, except when it comes to the idea of national pride. Conservative ideology often goes back to the idea of every person for themselves, and that if you are a good person you will be successful. Most important for conservatives are liberty and economic success, which they see as only possible through reduction of government spending. Liberal ideology is almost the direct opposite; increasing funding to public and social services, supporting communities and individuals, and seeing people as part of groups and communities rather than individual Americans.
I see this especially in my field of social work; we are taught to recognize that people are part of systems. There is no person who is beyond helping and individual failure doesn’t really exist, just lack of adequate and appropriate support at the intersection of vulnerabilities. Self-determination is possible and a great goal for many, but some conservatives I have talked to see things like welfare as negatively affecting the community rather than supporting vulnerable people to create autonomy. I, a liberal, see welfare as a vital (if currently flawed) service that the government should provide to lift up individuals and their communities.
3. Althusser sees ideology as a set of beliefs and framework for thinking about our role in society that we are taught to not question, not critically analyze, and which we must accept in order to be a member of society. This is true whether or not that framework actually benefits us. One example that comes to mind is the concept of the 9-5 job. Many of us would be happier and more productive with different working hours, but because corporations have an extant structure, we do not question it when employers expect us to work Monday-Friday from 9-5, because it can feel like there are no other options so how could we even imagine a world without the 40 hour work week.