For example, when TurboTax asks me what is considered US GOVERNMENT, it it asking out of what's in Box 11, or is it asking for what is NOT already in box 11?
CAREFUL HERE GUYS !
......for a 1099-DIV, the US Govt Bond interest/dividends that the software is referring to , will be be part of box 1a, depending on what funds you actually own. Box 11 is only for Muni's (or the US Territory bonds...Puerto Rico, Guam..etc)
The mutual fund you are invested in will provide that information on some paperwork they usually provide on their website for each mutual fund that has US bonds in it (usually as a PDF). They only provide a % of distribution for each particular mutual fund (usually a bond fund) and you use the % and the "Supplemental Information" on your consolidated 1099-B to calculate the exact $$ amount.
Here's how Fidelity delineates their US Govt Bond info:
https://www.fidelity.com/bin-public/060_www_fidelity_com/documents/taxes/2019-gse-letter-sai-funds.pdf