Why does America have "In God We Trust" on its bills?

lol it use to have "Gold Certificate" then when they changed the standard it said "Silver Certificate" now that were not on either standard it says "In God We Trust"

Because the ultra conservatives of the 50's believed that communists wouldn't use money that had the word god printed on it.

Stop laughing, I'm serious!

The same reason our Declaration of Independence has this:

When, in the course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the laws of nature and of nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable rights, that among these are life, liberty and the pursuit of happiness.

It's basically a way to inspire nationalism against communism, but seeing as how many people now see it as unconstitutional (as it is unconstitutional), it should change within the next few decades or so.

Because most citizens did trust in God at that time and a majority still do!!

America was founded on religious principles, as everyone SHOULD know.

Puritanical influence!

America was founded on Christian principals and values.

http://www.treasury.gov/about/education/Pages/in-g...

this explains it well