Indeed, birth certificates showing a child was born on U.S. soil are now proof of citizenship.

FORBES: Ending Birthright Citizenship Would Be Costly for Americans

The court ruling did not affect proof of citizenship requirements using the state forms.

NPR: Must Voters Have To Prove Citizenship To Register?

Further, these one-on-one scenarios improve decision-making between patient and physician and take out the need for insurance and proof of citizenship.

FORBES: Direct Health Care for the Uninsured

Recently, American border officials have begun demanding extensive identification and proof of citizenship from Canadians, an unprecedented tightening of what is supposed to be an open frontier.

ECONOMIST: Immigration in Canada

In some of these same states, including Alabama, Kansas, Tennessee and Florida, legislatures have also passed laws that demand proof of citizenship to register to vote (a tough deal if you don't happen to walk around with a birth certificate, passport or naturalization records in your pocket) or that reduce early voting.

CNN: U.S. voting rights under siege

The plan includes four key elements: stronger border security, creation of forgery-resistant proof-of-citizenship documents, fairer legal immigration for desirable candidates, and a "tough love" path to citizenship for those already in the United States.

CNN: Five reasons why time may be right for immigration reform