The Democrats have trotted out Alinsky's Rule for Radicals No. 4, in an effort to fend off legitimate outrage over Obama's usurpation of power on immigration. Rule No 4 is "hoist them on their own petard," or accuse your enemy of doing the same thing they are criticizing in you.
So, the arguments are out that both Reagan and Bush used executive orders to establish immigration policy, and Obama is only doing the same thing that they did. However, their argument is a lie (what else is new?).
There is a proper use of executive orders, to tweak existing legislation in order to implement the wishes of Congress. That's because small tweaks are easier to implement by executive orders than to run the whole legislation back through both houses of Congress to correct small errors or ambiguities. Both Reagan and Bush used executive orders properly in this regard -- with the knowledge and consent of Congress, to tweak legislation already passed. Unlike Obama, they did not misuse executive action in the place of legislation, as an end-run around Congress, to install sweeping new laws by the dictate of a totalitarian.
David Frum has more details on the Reagan/Bush executive orders in his article "Reagan and Bush Offer No Precedent for Obama's Executive Order." Read it at this link.
Don't be fooled by the Alinskyites in their efforts to justify fascism.