When the sweeping Republican tax bill was pushed through and voted into law just before Christmas, critics ripped into it as a gift for the wealthy. Many of them focused on the benefits that it will bestow upon the wealthiest of all -- the top 1% — and especially the top 0.1%. Critics worry that the ultra rich are becoming wealthier, while incomes for most other Americans are stagnant.Today's guest, Richard Reeves, says that the gap that poses the greatest threat to our culture isn’t the one between the insanely rich and the rest of us, but rather, it’s the gap between most people and the so-called Upper Middle Class, the top 20% of Americans, by wealth. That gap, Reeves says, is changing how families are structured and it’s informing our political and personal attitudes about everything. Richard Reeves joins Tom live from the studios of NPR in Washington, DC.