The United States is just one of many nations that offers the unconditional citizenship of children born within its borders. The following is a list of nation's that also grant Birthright Citizenship:
Antigua and Barbuda
Argentina
Azerbaijan
Barbados
Belize
Bolivia
Brazil
Canada
Colombia
Dominica
Dominican Republic
Ecuador
El Salvador
Fiji
Grenada
Guatemala
Guyana
Honduras
Jamaica
Lesotho
Mexico
Nicaragua
Pakistan
Panama
Paraguay
Peru
Romania
Saint Christopher and Nevis
Saint Lucia
Saint Vincent and the Grenadines
Trinidad and Tobago
Uruguay
Venezuela
NOTES:
NO European nations grant Birthright Citizenship except for Romania
Canada is the only developed nation other than the United States
NO nation, other than the United States, has more than 200 million people
Every nation has fewer than 50 million except the United States, Pakistan, Brazil and Mexico