Here is a worthwhile 30 minute podcast by Rabbi Yaakov Shapiro:
He raises some questions we all should be asking ourselves.
Especially important to me is the claim that no Christian can be a Jew. That has a direct bearing on the "two covenants" theory, as it appears to mean that Jews believe that Christians have no right to be in Jerusalem.
If that's the case, then why are we funding the Zionists? Let them build their own holy city and pay for their own wars.