Not really since people trust the United States. It's why treasury T-bond yields are so low, the United States government commands a great deal of respect. Their word is credible.
What does T-bonds yields have to do whether the US has done any cover ups?
T-bonds yields are low because most of world trades and finances are still conducted in USD so there is always huge demands for USD, and that the world (at least for now, although for how much longer it is still open for debate) still has confidence that the USG will be able to service the debts.
So as long as USD is still used much for world trades and finances and the USG can contain their inflation and keep domestic economy afloat, the confidence is still there.
But for certain, sooner or later, the influence of USD will wane, because other economies will get stronger in relative to the US (you don't think US will remain superpower forever, do you?) and they may want to use more and more their own currencies: yuans, euros or what have you.
This, coupled with weak US economy and burgeoning foreign debts will make T bills much less attractive.
Now back on the topic on the question whether we can fully trust the USG, in the past decade there have been flurry of declassified CIA documents which pointed to the US involvements in supporting military coups in many countries in the late 60s and 70s (including in my own country, indonesia), where the USG has previously denied.
Remember also the Contra scandal?
Only a fool can fully trust their governments.
The USG will always need to assert their political and military power in the world to keep their superpower status which have positive impacts on their economy.
But it won't last.
Mark my word
