There were practical reasons. This is just a cameo picture, not a complete explanation, but perhaps it will serve.
The Masons (Masonic Order) was a somewhat secretive organization that required oaths to advance within the ranks; the more one advanced the more solemn the oaths - and the implied penalties. Such a structure automatically lent itself as useful to a paramilitary organization.
In colonial times civilian militias were common - and necessary, especially on the rural frontiers. Again, the local Masonic Lodge was a natural gathering place for such paramilitary organizations.
With the outbreak of the Revolutionary War once again the Masonic structure offered obvious advantages. If General Washington needed to send a unit into the western frontier areas for some military or intelligence mission, who better to trust as the paymaster than a Masonic brother who hopefully would not disappear with the finances into the uncharted forests?
Thus, from the earliest stirrings of insurrection right through the end of hostilities the Masonic Order served as a natural human structure in support of Colonial security needs.
The Masonic role in the Revolution has never really received the attention it likely deserves, but apparently the Masons are content to leave it that way.
Thank you for some Masonic history.
(I hope you are feeling very well!)
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