The US constitution. Thought it said US in the post itself, but I suppose it technically didn't clarify
In any case, they more than 99% likely mean the US constitution given how US-centric social media is, and how the US constitution's start of "we the people" is fairly well known in the US
Sure, not knowing it's the US constitution is reasonable if not from the US
However, I think one could take a reasonable guess that if the first word of a constitution wasn't a pronoun, this post probably wasn't about that specific constitution
Why would someone post something like OP without stating what constitution it is? Do they expect only americans to read it? Maybe keep your american jokes in american specific communities.