On modern gun design:

What has been will be again, what has been done will be done again; there is nothing new under the sun.

Ecclesiastes 1:9 NIV

But this time, we're gonna do it betterer!

https://www.youtube.com/watch?v=rblfKREj50o

Ecclesiastes said:

What has been will be again, what has been done will be done again; there is nothing new under the sun.

That is an understandable view considering the reputed writer lived in a time period when sword and spear had been the standard infantry weapons for centuries.

Three millennia later, things have changed a bit.  

"Close, engage, and destroy" is eternal.

farmplinker2 said:

"Close, engage, and destroy" is eternal.

You make the same mistake Ecclesiastes did.  Just because up until the present infantry have had to "close, engage, and destroy" has been true, does not mean it always will be.

YouTube

Horror Short Film "Slaughterbots" | ALTER

In a dystopian world a new form of A.I. weaponry has been created. All these drone bots need is a profile: age, sex, fitness, uniform, and ethnicity. Nuclear...

Millennia from now, when humanity is a bunch of computer programs created from scanned human brains, General zepxxxr:V65.03 will be telling its subordinates, "You can't snipe at them, get to knife fighting range"! 

And his troops will wonder why their combat techniques are being compared to a wetland dwelling bird, and why you would use an eating utensil as anything other than a desperation weapon.:)

We'll be using M2s in the Alpha Centari conflict.