Barack Obama's administration has said it has no evidence that extraterrestrial creatures exist in response to a White House petition signed by over 5000 people demanding that the White House disclose the government's knowledge of extraterrestrial beings. More than 12,000 signed another petition seeking answers to the question of an extraterrestrial presence engaging with us humans.
In response, Phil Larson of the White House office of science and technology policy, said that the US government has no evidence that life exists outside Earth, or that an extraterrestrial presence has contacted any member of the human race.
As someone who strongly believes that out of the trillions and trillions of stars, it would be improbable that there isn't life evolving on one of the rocks circling them although many disagree. The main reason being why have we not seen them?
I answer simply because if they did take a look at us, they would keep their distance because to an outsider we must look like the last race in the Universe anyone would want to to make contact with.
Taken as a whole, we are not a peace fearing people by any stretch of the imagination. Our whole history is one of war and oppression and developing bigger and better weapons to kill each other with. We have wiped out entire species and been daft enough to seriously pollute our own environment.
If we came across another species and it was setting about doing the same thing as us, we would back off and avoid it and if the aliens have any sense at all, they have done the same thing and scarpered back to whence they came with the message of giving that blue planet a miss, they are crazy.