1. No. It's not legally enforceable in India as your wife didn't contest the Divorce and exparte divorce passed by US court cannot be enforced in India
2. No. As you are still legally married to your wife and if you marry again without getting a decree of divorce from Indian courts having jurisdiction, you will be committing an offence of bigamy Under section 494 IPC.
3.No. As it is been passed by a court having no jurisdiction to entertain such a matter, therefore the judgement passed by the US Court would not be taken into consideration.
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