Deconstructing the statement : "Generous public investment"

"Generous public investment in X" (Choose any X you wish.)

Generous: whatever the merits of the proposal in question, forcibly taking people's money to pay for something is not an act of "generosity" either by those forced to pay or those doing the forcing. Call it what it is: we're going to take money from some people and spend it on things that benefit (normally a small group of) other people.

Public: this word obscures the fact that all of the funds that governments spend must ultimately come from "private" individuals. The investment in question is not the mysterious public doing something. "Publics" don't act. Individuals do. Again, perhaps this proposal is worth doing, but let's be honest about how this works.

Investment: this word implies that the expenditures in question will generate some sort of return, presumably in excess of the expenditures. This is often precisely the point at issue, so the case needs to be made without begging the question. Add to that the fact that almost every single government program, especially major ones, you can name has ended up spending WAY more than projected when passed, and you can understand why some might be skeptical of using the language of investment and the implication of a return above cost.