How did the maxim automatic machine gun change society?

Answer 1

By altering the battlefield into a far more deadly place of mechanized death, the Maxim gun made war far more costly than ever before, and thus made many countries more relcutant to send their young men to war knowing that this weapon would mow down hundreds of them.

Alternately, the machine gun made mass murder far easier to achieve and more accessible, you no longer need an army to do it.

The adoption of the Maxim gun by the British Army changed the tone of its colonial affairs. The sheer mass of firepower it offered made it much easier to subjugate colonial natives.

From a military standpoint, the machinegun changed infantry tactics because it was now relatively simple for a small number of machinegun-equipped soldiers to defend against a very large number of attacking infantry. The machinegun caused defensive tactics be much more successful than offensive tactics. It became much easier to hold ground than take it.

As noted above, the machinegun (in combination with the bolt-action rifle) allowed colonial powers (Britain, France, Germany) a huge advantage over native folks, which meant that very small numbers of colonial soldiers could fight and conquer vast countries in Africa, India, and Asia cheaply and quickly.

Unfortunately, the very first answer above is decidedly untrue. Native uprisings continued well after the introduction of the machinegun, with a universal outcome of the colonial power killing large numbers of the natives. In addition, the European countries which had the machinegun (and used it on their colonies) failed to re-think their own military strategy when fighting eachother. The mass slaughter of WW1 is a direct result of this failure - WW1 generals were still using Napoleonic tactics where the offense is stronger than the defense. Sadly, the machinegun (and other recent technologies) gave the defense the stronger position, and thus using offensive tactics were a great failure. Only after WW1 was over did countries really absorb the less of the power of the machinegun.