Being open minded or honest isn't a priority of the left, winning elections and getting new voters is.
What's the point of having borders and laws if you are going to incent people gaming them? Regardless of what the US does (and it doesn't physically harm people at the border who aren't violent themselves), people have a choice, since the US is its own country with its own laws and the outsiders aren't part of the country. Why would you want people who don't care about their kids, coming to America? Given this paradigm, and people know what the rules are, the "parents" are actively choosing to be separated from their kids. That means they are low-lifes. But remember, it's always Americas fault, even when outsiders break Americas laws.
Anyone who falls for this emotional crap, which has been going on for years (they didn't show Obama era kids crying, I wonder why), is a pawn for the media and the leftist crap. The question is why they are doing it right now. Well, here's why:
1) Mueller and the Russia probe is now clearly a fraud and losing subject
2) North Korea situation is another president winner
3) Economy is doing just fine
When you're losing and a big election is coming up, you better try the old emotion card. What a fraud, too bad they're gonna lose again