Now What ?

One issue that the 9th Circuit Judges raised was what was the risk that precipitated the Executive Order.  The judges were willing to take such evidence under seal if it was such that it could not be publicly reveled.  The government presented no such evidence.
Trump has continued to talk about the need for this ban due to the risk of terrorism.  He has being saying that he wanted such a ban from early days of his campaign.  He has being saying this from the time before he received his first high level security briefing.  His most memorable campaign comment was that he wanted to ban Muslims entering the US "until we can figure out what the hell is going on".  Well, how could he have figured out anything when he had practically no high level staff and had been in office for about seven days?  Especially to promulgate such a vast reaching order as to include green card holders.
If Trump truly believes that there are suddenly circumstances that put American safety at immediate risk, then he has an obligation to draft action to address that risk.  If he chooses to wait out the judicial process, then he doesn't have much of an immediate concern.
My belief is that Trump glibly tried to fulfill a campaign promise by disrupting thousands of lives without legitimate legal foundation and damaging, perhaps irreperably, American relations with the broad Arab world.  He also lied about the extent of the impact in terms of numbers of people affected and he lied when he characterized the implementation as being smooth.
We can only be thankful that he learned a limit on Presidential power before his actions got any worse.