Zionism is inherently an at least somewhat racist ideology, as all racially-based nationalist ideologies are.
First of all, Jews are most certainly not a race. Secondly, you realize zionism is just supporting the existence of a Jewish state. If Israel being a Jewish state is wrong, how about the 25 countries with Islam as their official religion? The 6 countries with Buddhism as their official religion? And the 11 countries with Christianity as their official religion?
1.Presumably, being a secularist, Lief would want those to not have an official religion as well.
2.Zionism (or zionism in as far as it has a meaning today) isn't supporting the existence of
a Jewish State, but rather the existence of
the Jewish State of Israel.
3.I don't see why judaism shouldn't count as an ethnicity or rather I can't see how you can consider 'African-American' to be an ethnicity and 'Jewish' as not constituting one.