Ok, it was an "executive branch memorandum", which has exactly the same effect as an EO. It directed the executive branch to ignore federal law and refuse to prosecute everyone in a specific category of illegal immigrant. You can argue that it was just an exercise of "prosecutorial discretion", but the courts don't agree with you as they've refused to allow the current administration to rescind it. In fact, one might argue the courts have actually taken that "memorandum" and turned it into irrevocable law.
The Republican Party has shifted hard left in the last twenty years, the Democrat party most certainly has not shifted right. Many Republicans in the Senate (and probably most of the house) could credibly just change to Democrats and nobody would even know the difference, and that's because the Republican Party has totally abandoned its roots. There are a few outspoken outliers, of course, but there has been essentially no actual conservative anything in the US since Reagan. JFK would never win the nomination as a Democrat today (for that matter neither would Bill Clinton), he'd have to run as a Republican as he would be considered far too conservative.
I remember Reagan, I'm guessing you don't beyond whatever caricatures your college professors sold you on, and you're looking at this solely through the lens of "oh my god the country isn't liberal enough", as most people on the left do. Reading your comment history tells me that's where this discussion is going and I won't bother to participate further.