Let us start with some simple aeronautic dynamics, using an analogy that my PIMCO colleague, Bill Gross, came up with to describe the economic risks facing the American economy. For the Dreamliner to take off, ascend, and maintain a steady altitude, it must do more than move forward.
让我们从一些简单的航空动力学开始，用我的太平洋投资公司（PIMCO）同事格罗斯（Bill Gross）所做的比方来描述美国经济所面临的经济风险。梦幻客机想要起飞、升空然后维持稳定高度，光是向前运动是不够的。它必须向前运动得足够快，超过某个物理临界阈值——远高于绝大部分波音其他型号（体型更小）的飞机。