If we knew aliens were coming to land on Earth, should we destroy them before they land? Why?

I've recently written about extraterrestrial biohazards. The big issue: Do the ETs have 'normal' biochemistry or mirror-image biochemistry? If its the latter, then whatever bacteria they carry on or in their bodies would have a very difficult time infecting us.

For example, we have mostly L-amino acids. If the germs have mostly D-aminos, they could not use ours as building blocks for replication.

A much larger issue for alien visitors with mirror image biochemistry: the photosynthetic microorganisms--like cyanobacteria--on the bottoms of their shoes. If these beasties find their way to the ocean, they'd be a problem in the intermediate term, because at the moment we wouldn't have anything that could eat them.

If the UFO aliens landed in Arizona or in Alabama, with their paranoid immigration laws, they'd probably get shot. In most other places, reason would probably prevail. If the aliens with mirror-image biochemistry take off their shoes, and put on some Earthly ones, there should not be a big biocontamination risk.

We have no idea what someone from another planet may be carrying but I know the US government does and if they come again they will handle it again I am sure and keep it under wraps so unless they decide we should have what these extraterrestrials have then we don't have to worry.

I would actually have to assume they are hostile and take defensive measures. The only way to avert conflict would be if there was some sort of contract prior in which an agreement was reached and we set a meeting place on the moon first and exchange guidelines. Then they'd be able to migrate towards earth.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.