Purpose of に in 政治に興味がある

Question

政{せい}治{じ}に興{きょう}味{み}がある。I am interested in politics.

What is the purpose of the に particle here? I would have said it with は (As for politics, I have an interest in it) or が (politics is what I have an interest in).

Thanks in advance.

Answer 1

So in Japanese, the way 興味がある is used when saying you have an interest in something is usually with に. Nに興味がある as in "I have an interest in N." Of course, you may also use は and が, but in like Intro to Japanese classes, に is the "proper" way to connect a noun and 興味がある.

PS. I use the term proper to mean "this is the way they taught us and if we used a different particle on a test we lost points for it."