@evrr in addition to what I said above, the question here becomes
(a) since as a citizen of US you will have to file US return, do you have any need to file jointly with your wife? If you do then she will need a tax id ( SSN or ITIN ), she will have to request to be treated as a resident alien and of course her world income comes under US tax. But this also means that if your tax home is India, you each can use Foreign Earned In come exclusion to exclude " active" in come ( up to the max allowed each year ). Passive income cannot be excluded but is eligible for foreign tax credit/ deduction etc. type of treatment.
(b) If she has only passive income ( from US sources) and is taxed in India then this must be resourced under treaty to claim foreign tax credit.
There are too many paths based on the facts and circumstances of your case. I need more details from you.
If the details are not of interest to the general user , you are welcome to PM me with details of your situation ( what types of incomes are involved, is there any active income involved or are you both retired, do you have US pension / SSA etc. -- the more detail the better ) -- just no personally identifiable information.
I look forward to hearing from you
pk
