Both Iran and Israel are essentially theocracies.  Neither political system can function without the approval of its most radical religious conservatives.  

The primary difference is that Israel tends to keep its concerns internal to the land it won through bloody warfare in 1967.

Iran seeks a Caliphate now and world domination by Shi'a Islam as their ultimate goal.  That requires them to take over the entire Levant now and the rest of the world later--Insha'Allah.  (As God wills it!)  

The Levant basically includes  Egypt, Iraq, Israel, Jordan, Lebanon, Palestine, Syria, and Turkey.  That is the Iranian short term goal.  

With oil now so much more readily available in Canada and the US, is it still in our national interest to be involved in the Middle East?

In "realpolitik" what effect if we no longer support Israel?  Israel is a nuclear power; can we afford to ignore them?  Or are they the best way to deter Iran?