The president is set to speak to the nation tomorrow, Thursday, at about 8 p.m.

It is widely expected that he will legalize about five million undocumented people, many of whom have children who are American citizens.

There will also be other immigration orders in his executive action.

As everybody knows, this is extremely controversial and a new NBC-Wall Street Journal poll out today breaks it down this way:

Do you approve or disapprove of the president taking executive action on immigration?

• 48% disapprove
• 38% approve
• 14% have no opinion or are unsure

Putting emotion aside, the issue is not really about five million undocumented human beings.  It's about President Obama challenging the Constitution.

Talking Points has said it before, the president should wait and give the new Congress a chance to pass a fair immigration law.

If it does not, Mr. Obama's legal position would be stronger if he takes unilateral action.

But the way things stand now, surely the president will lose in the courts.

I believe Mr. Obama knows that and well understands how divisive his actions will be.

But he doesn't seem to care and history will not look kindly on a sitting president causing a constitutional ruckus.

Trust me on that.

And that's the memo.