From a religious point of view, rainbows are meant to be a sign from God which is a promise that he will never flood the world again like he did in the days of Noah. In norse mythology there is a rainbow bridge used by the Gods and giants that is destroyed at ragnarok.
If you are looking for a mind control perspective, the term "over the rainbow" refers to the wizard of oz which is a film they sometimes use to program slaves. If someone is going over the rainbow they are disassociating from reality to escape the horrific torture that is often used by the brutal MK system.
Scimitar do you actually know this guy? It seemed like he/she was asking a genuin question to me.
A fool thinks himself to be wise, but a wise man knows himself to be a fool – William Shakespear