A lot of us have spouses who do not come from Spanish speaking countries. Only about 15% of the US population speak Spanish, and many of those also speak English. English is, by far, the most spoken language in the United States. Sure, you can come to the US and choose not to learn English. Your career options will be limited to companies where the ability to speak only Spanish is acceptable. You will not be able to shop in stores unless there is at least one person there who can speak Spanish. You will also not be able to become a US citizen, as fluency in English is required.
English is the de-facto language of the United States. A lot of doors open up for immigrants who can speak English.