Do you believe in UFO's?

NPR was doing a re****t on UFO data this morning.  It got me to
wondering ...

Many UFO believers think the government is hiding UFO data.  In 1950,
the classification was higher than the "Top Secret" hydrogen bomb
(according to today's radio guest).  Perhaps the UFO belivevers of
AFCA can help me understand some things.

Why bother to keep it a secret?  Is the government keeping it from its
own citizens or are they hiding it from North Korea?  If we are being
visited by aliens, wouldn't it be better for the entire human race to
form a united front?

If the aliens landed in New Mexico or Nevada, they must have they
landed in Argentina, or Kenya, or Iran as well?  Are the Argentinians,
Kenians, and Iranians hiding it too?  How many people are "in" the
know?  Are all the governments in on the conspiracy?