Conversion to any stream of Judaism is not fast. Potential converts must typically spend many hours of study under the supervision of a rabbi before they face a rabbinical court, a beit din, which will determine whether they can convert, then, Jewish tradition requires males be circumcised and all converts to immerse in a mikveh (ritual bath) before the beit din finalizes the conversion. Conversion is not just a matter of accepting a set of personal beliefs, it is about becoming part of a community and taking on obligations within that community. As such, conversion to Judaism can be compared to becoming a naturalized citizen of a country. Details of the conversion process depend on the community. Some large communities have formal classes for converts, with a fixed curriculum, while in smaller communities, converts study one-on-one with a rabbi. Regardless of the community, though, the first step is to consult with a rabbi!
According to Jewish law, a Kohen can't marry a convert to Judaism.
He didn't.
Nothing. Jews do not seek converts. If a person wishes to convert to Judaism, they are permitted to do so, but Judaism teaches that Judaism should not be proselytized.
No, Obama is a Christian.
yes
Yes, according to tradition.
Only Judaism
A new Jew.
His father is a convert to Judaism and his mother is Jewish.
Lots of reasons. One is that Judaism doesn't believe in encouraging people to convert. If someone wants to convert to Judaism, they're welcome to (although discouraged at first), but Judaism has no mass programs to get people to convert. Nor did it usually have forced conversions like the other religions did. Another reason is that Jews have been heavily persecuted over the years and many were killed.
His father is Jewish and his mother is a convert to Reform Judaism.
Jewish people would call it apostasy.