If Israel's a home for both Jews and non-Jews, why aren't non-Jews represented on Israel's flag or anthem?

For the same reason that the American flag and anthem don't incorporate minorities such as Chinese, Japanese, Muslims etc.

Sooner or later, those 20% will outnumber the Jewish residents and Israel will have to do what it did in 1948. Yes i am talking about some ethnic cleansing. Actions speak louder than words, just because they say it doesn't mean they are... Everyone lies!

Not applicable since there is no such thing as "Israel" in the first place for "it" to have a flag; what you see here:http://www.google.com/search?q=Zionist+flag&rls=com.microsoft:en-us&oe=UTF-8&startIndex=&startPage=1&rlz=1I7RNWN_en&safe=on&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1215&bih=605 is the flag of Zion.

The Israeli government doesn't even treat black Jews like equals, they treat them like inferiors. So if that happens, how much more for non-Jews?

Oh, I would be very happy to see Muslims moving to Singapore from Israel. The Muslim population of France is 15%. Ask french to include "Allah" Akbar" in their Anthem. And don´t forget to ask Americans why they did not put the tomahawk on their flag. Israel is the home for Jews. And its Flag and Anthem reflect this reality. Others can live in Israel and enjoy the same civil rights if they agree with this. Someone does not like it? He is free to live any moment.

for the same reason, we, the USA, have 1 flag and anthem in all states and we are home all almost all world nations, http://www.google.com/search?q=us+flag&hl=en&rlz=1T4SKPB_enUS378US378&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=m-AZTveHOYf40gGctKGXBQ&ved=0CE8QsAQ&biw=1327&bih=484

Lots of groups aren't represented on many flags. One issue that the flag of Israel has a dual function: It can serve as a tallis. So, while the Star of David is appropriate, other religious symbols might not be, as the flag can be a religious garment. And it is actually worn that way more times than you think. As for HaTikva, I do think the lyrics need to be tweeked a little.