There are two main drawbacks. The first is that you and any children you bare will be liable for service in the Israeli Army. The second is that several countries will not allow you entry.
Yes. In fact, even if only one of the parents is Israeli then the child is considered an Israeli citizen.
If it's a valid US passport or you are a dual-citizen most likely
NO
palestine
Are you not familiar with the Law of Return? All Jews have an automatic right to immigrate to Israel and to be Israeli citizens. That is the fundamental reason for the existence of Israel, to provide refuge for all the Jews of the world.
Anyone can become an Israeli citizen except for an ethnic Palestinian who did not live within the Israeli borders in 1949 or is not in the annexed territories (like the Golan or East Jerusalem). This caveat is due to the sensitive political nature of the Israeli-Palestinian Conflict. In fact, Palestinians are the single largest Israeli citizen group after Jews. It is far easier for a Jew to become an Israeli citizen, than a non-Jew, but this is typical of countries in the region which give individuals of the dominant ethnicity from abroad to become citizens. (Armenia, Lithuania, Poland, etc. have this rule as well.) There is criticism that the inequality of citizenship process times is problematic, but it is much easier for a Muslim or Christian from abroad to become an Israeli citizen than it is for a Jew or Christian from abroad to become a Moroccan or Tunisian citizen and a non-Muslim can never become a Saudi citizen.
YES
There is no current Israeli citizen in U.S. Congress. There are certainly many pro-Israel Congressmen in both houses, but none of them have Israeli Citizenship.
Yes, if she has an Israeli Passport, if she has an expired US visa or something else doesn't really affects to her marriage process and also Israeli citizens don't need visa to Canada even if she travels from USA.
In general, Unless your parents are not citizens and don't want it, you are a citizen of the country in which you were born.
she have to marry again in israeli
Anyone can become an Israeli citizen except for an ethnic Palestinian who did not live within the Israeli borders in 1949 or is not in the annexed territories (like the Golan or East Jerusalem). This caveat is due to the sensitive political nature of the Israeli-Palestinian Conflict. In fact, Palestinians are the single largest Israeli citizen group after Jews. It is far easier for a Jew to become an Israeli citizen, than a non-Jew, but this is typical of countries in the region which give individuals of the dominant ethnicity from abroad to become citizens. (Armenia, Lithuania, Poland, etc. have this rule as well.) There is criticism that the inequality of citizenship process times is problematic, but it is much easier for a Muslim or Christian from abroad to become an Israeli citizen than it is for a Jew or Christian from abroad to become a Moroccan or Tunisian citizen and a non-Muslim can never become a Saudi citizen.