The financial markets only bought US treasuries under those conditions because they were the least bad option during risky moments. There's no law of physics which says that will always be the same.

Trumpanomics is trying to weaken the dollar to make us more competitive as an exporter (along with tariffs which make imports into the US less competitive with domestic goods) and he is Trump's Congress is blowing away previous deficits, so investors are wise to reevaluate their previous risk mitigation strategies.

The Yen Carry Trade is now fully in reverse and both JP and US are going to see higher interest rates, causing both of their debt service to take up an increasing slice of the budget pie.

Investors are jumping into CN bonds now and are likely to look to the rest of the BRICS nations as the IS looks increasingly unable to manage a responsible budget, an economy that doesn't seem to be growing much, and sovereign bonds which have fewer buyers today than a month ago.