We don't have to imagine at all
Since the 1960s, the US has spent trillions (yes, with a "t") on various "wars on poverty." We've had dozens of government programs like low income housing, food stamps, WIC, and countless others, but the official poverty rate is pretty much the same as it was in the 1960s. Perhaps they're defining down what the official poverty rate is to justify the continued funding, or perhaps all those trillions in programs simply have not worked. I guess we should admit defeat since it appears pretty obvious that the current programs aren't working.