Jerusalem is the capital of two states. Plain and simple. Bush promised the same thing. Obviously, the underlying national security issues of the situation aren't made clear until one is president. Maybe you don't know it, and maybe you do, but it's not just that the last 3 presidents(since congress approved it in 1994), haven't moved the embassy, it's that every 6 months they sign an executive order, or the like, which prevents it from being moved for the following 6 months. This has been going for the last 16 years or so. Bush signed one a month or so before he left office.
Militants loyal to Islamic State claim suicide bombings in Nigerian capital (Reuters)
from the article: Dershowitz: Obama needs hard line on Iran to win Israeli support