India does not allow Dual Citizenship. But you can apply and get a passport-like booklet, at the nearest embassy and consulate general, that will allow you to travel to India visa-free.
The US recognizes dual citizenship.
she have to marry again in israeli
By law, the US doesn't recognize dual citizenship (i.e. constitution prevents dual nationality) but somehow it always does recognize it.
No. The US president MUST have US citizenship only.
Yes dual citizenship is allowed for US citizens.
Not necessary , now Indian govt. supports dual citizenship so migrating to Australia does not mean that you lost your India citizenship
Yes.
Spain does not have dual citizenship agreement with the US.
If you apply for citizenship in another country your US citizenship is automatically revoked. The US does not recognize dual citizenship. You revoke it in writing at a US embassy, outside the US.
If you have dual citizenship, yes you can.
He will become a dual citizen of the uK and the US.
You can apply for dual citizenship to the USA and almost any other country. Many more people than you might think hold dual citizenship. But the road to dual citizenship, with only a few exceptions, is long, twisting and full of "gotchas".