- the Wikimedia Foundation, and
- you personally.
United States laws apply to the Wikimedia Foundation (which owns Commons). As a result, the Wikimedia Foundation insists that all user comply with US laws.
Which laws apply to you personally depend on which country (or countries) you are a citizen, national, and/or resident of. If you are a US citizen living in the US, then you must comply with US laws. In all other circumstances, users must comply with both US laws and whatever local laws apply to them.
Commons does not provide legal advice. If you need help figuring out which laws apply to you, then you need to seek competent legal advice.