The problem has been hanging there since the GFC 2008. The world is trying to see how much of debt a reserve currency can take on before it actually cracks.. Confidence seem to be going stronger and stronger (as seen by the high S&P index level, and low UST10y cost) so no reason to be too much of a doomsday view..
I think nobody really know if this actually cracks, then how fast will things deteriorate.. is it like the famous: "Gradually, then suddenly.” ― Ernest Hemingway, or will there be a graceful degeneration.. With such high leverage factors in the market (property, stocks, bonds)... makes sense that the 'suddenly' will be really sudden.. but still, its nothing we have experienced before so can only wait and be audience...