The truthful answer - that the lefies on here are carefully avoiding is that indeed they would be happy for those illegal gang members to be returned. They just don't want their party to take the blame for it.
They want Trump to fail, and fail hard in his quest to make Americans safer, the government more fiscally sound, and working people more prosperous. But they want the courts to be the ones to say that cutting spending violates the constitution and so does deporting illegals.
That way their next presidential candidate can promise to deport and cut spending, but to do it the legal way. Then never do it.