Can the Country Code field be removed altogether?

Summary: Phone Country Code Field - Removal

Content (required): All our Accounts are in the US so there is no need to identify a Country to distinguish #s that are outside of the US. In addition, our Users must remove the default value in the Country Code field in order for the Phone # to appear in the correct format in other integrated systems. Is it possible to just remove the Country Code altogether so that only the Area Code, Phone # & Ext fields remain? If so, will removing the Country Code field cause any downstream issues with the new Phone/Email Verification Services if it