Make the calculation. How many people have been saved by bullets and how many have died by it.
And those that have been saved did they had to kill anything in order to be saved?
A quick question... how do you propose groups of people like Nazi-led Germany be dealt with, then?
A bullet is a thing. A tool. Steel is a waste of material. It's been used to kill people for centuries.
When I load a firearm - you can rest assured that I will never level it at you without justification or to satisfy my own ambitions of power. Other people are not so disciplined - and those are the people I will more than happily put bullets in; because the society you and I both enjoy cannot survive so long as those types of individuals are allowed to utilize the advantages afforded by economics and technology to subject others.
I don't care which design they choose from what film, enterprise or a deathstar operated by a HAL 2012, i just want to go climb the mountains on Mars
That might be a bit longer in the making. A space ship to get to mars is only half the equation... a space ship to get you off of mars is a little more involved of an affair. One must escape Mars' considerably stronger gravitational field (compared to the moon) and atmosphere. You're looking at a mini-shuttle necessary to get you back to your ship (unless it's rated for atmospheric performance... in which case it can't be an oxygen-breathing engine that it utilizes).
I would like to look into developing a VASMIR-type engine that can be used in three modes - having an ionization, heating, and compression phase powerful enough to work in an atmosphere; an exospheric mode (where a gas stock must be used) and a Hydrogen-Beryllium injection system with a magnetic deflection unit capable of inducing hydrogen-beryllium fusion via pulsed compression with directional release (a military application - similar to "afterburn" for high-impulse maneuvers).
The concept is derived from plasma-focus fusion.
Of course... the key obstacle to long-term space operations rests in the difficulty of simulating gravity. We evolved to function with gravity... we encounter complications when working without it. We need to be able to produce a gravitational field at will or to emulate a similar universal attractor.
I see spinning space ships as a begrudgingly accepted compromise on the issue.