Are they trying to trade or to provide stable long term investments for pension funds or make sure the investments in banks can be withdrawn, in addition to making sure the currency maintains its value?
i do not agree with this. if the government continues to borrow, the debt will become too large, which will force the fed to cut interest so that the government can pay back the borrowing cost, at that point, fewer people would buy the debt, thus the fed will buy the debt itself, that means, fed will print more money. with fed printing more money, the asset price will go higher, which ends up even fewer investors will buy debt at low interest. the cycle becomes worse and worse with time moving on. the new AI technology will force more people out of work, thus less tax the government can collect, not nice picture in the future. this debt nightmare will not be solved in a democratic country since no leaders can cut back the welfare the poor has entitled.
Even if the interest rate falls the amount that is owed will continue to increase so even with the reduced interest rate the debt repayments will rise. $1,000 at 2% interest and $10,000 at 1% interest the repayment has increased even with a lower interest rate because the principal has increased.