We do need to do something. This isn't fear mongering, DACA is a temporary reprieve from deportation. Our President likely will just not renew it. All DACA recipients knew this, surely they were prepared for it long ago? No different than renewing any permit or license. Sometimes they are denied.
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Snips from USCIS, Consideration of Deferred Action for Childhood Arrivals (DACA)

You may request DACA for the first time or renew your existing period of DACA if it is expiring...

On June 15, 2012, the Secretary of Homeland Security announced that certain people who came to the United States as children and meet several guidelines may request consideration of deferred action for a period of two years, subject to renewal. They are also eligible for work authorization. Deferred action is a use of prosecutorial discretion to defer removal action against an individual for a certain period of time ...

https://www.uscis.gov/humanitarian/consideration-deferred-action-childhood-arrivals-daca