Trump's second top tactic is to foster fear. As yours points out
"The official position of the Trump administration is that any unauthorized immigrant in the US should be “looking over [her] shoulder” and worried that ICE will come after her at any time. The biggest change to policy under Trump hasn’t been the scope of deportations or even of arrests — it’s been the aggressive messaging that anyone could be next.
Local and state officials who see unauthorized immigrants as part of their own communities, and who are concerned about the effects that targeting unauthorized immigrants will have on their legal immigrant neighbors and US citizen children, are trying to combat that fear.
Laws that force ICE to put more effort into arresting and detaining immigrants are one way to do that. Simply sending the message that some politicians are looking out for immigrants and fighting for them is another — probably not as effective, but something nonetheless.