回复：其实我和你的看法一致，只是不同意你的说法

"关键是举债后的资金使用的有效性上"

Research done by scholars (one of them named Rogof?) concluded that 92% of GDP is the threshold beyond which increased borrowing will impact negatively on GDP.

US government debt is now just over 100% GDP.

Borrow to grow is only effective when your debt level is still not too high.  The US is traveling along toward a dead end.