I am not a scholar on Sikh history, but this is how I imagine Akaal Purakh's fauj impacted the world when the khalsa was at its spiritual height centuries ago:
The Khalsa would travel throughout the land, through jungles and hard terrain, singing Akaal Purakh's praises wherever it went. The sounds would penetrate the air, bringing peace to the pitiful creatures living in the harsh forests. Who knows how many animals got mukti just from hearing the chardeekala kirtan of the Khalsa Fauj? Wherever the Khalsa went, dry wood would turn green, and the earth would bloom beneath its feet.
As the Khalsa travelled, sick cripples, people lost in sadness, beggars, would tumble across their path and be shot by the arrows of love. They would allow themselves to become initiated into Akaal Purakh's army, and suddenly the impoverished people of the world would become empowered warriors.
Wherever the Khalsa would establish itself, building Guru Ghars under Guru Sahib's hukam, there thousands of needy people would begin to come. The Khalsa, following Guru Sahib's orders and maryada, would distribute amrit-filled langar, and so many hungry people would be satiated from the naam-filled food. The gurbani flowing from the keertanis, would cure the sick, and even the sarovars would serve as a healing pool.
Guru Sahib's Khalsa is perfect. The Khalsa will rise again and serve the world as it does so. By obeying the commands of Guru Sahib, by being a khalsa which lives strictly according to Guru Sahib's rehit, by conducting all affairs in accordance to maryada and not compromising on that, and most of all,
by lovingly dedicating ourselves with to naam and gurbani in every moment of our lives, we will once again become a Khalsa that stands over the whole world as a guardian and protector.
Vaheguroo!