I don't know Cruz's position, but just like the rest of the Conservatives, I can predict it:
It is not the declaration of emergency.
It is the denial of the House's right to the purse, and redirecting money that is otherwise allocated.
We wouldn't be at this place had Trump not allocated that money in that bill that promoted amnesty. The bill which he signed that gave him only 1.3 or whatever the number was. He signed onto that. He should have never signed that piece of garbage. If he wanted to declare the Emergency Declaration it should have been because he couldn't sign a bill that didn't promote border security. And I am sure that McConnell was well aware that he was going to drop this declaration as soon as Trump signed the bill.
What gets me is all these "allways Trump" people who cannot own the situation. Trump ruined any chance of border security by signing the bill. Then he says as he is ordering the Emergency Declaration that he didn't have to. Well he did but the order was wrong. It should have come after he vetoed a bill that was a bloated gift to open border liberals. Which he didn't do.
Don't blame Cruz, Sasse, Tillerson, Paul......etc. I do see the Constitutional argument even though I wish that Trump could build the wall. Actually I am nearly over the wall. Because it is just sections of waste. If you want to build a wall it has to be a full length. Which brings us to what Trump has accomplished on border security. Nothing.
Can you imagine the wall in Israel that we use to say walls work with gaps? Can you imagine if they allowed the Palestinians to dictate where they wanted a wall? Same thing Trump did when he gave local governments the right to say no to the wall. A wall doesn't work if its not a wall.