Illegals are not 'subject to the jurisdiction' of the United States unless a misinterpretation of the Constitution is applied. They are citizens of and subject to the jurisdiction of whatever country they came from. It in no way intended that their children be citizens because they managed to get into the country illegally or any other way. The 14th amendment was originally intended to give citizenship status to the freed slaves."Subject to the jurisdiction thereof" is the catch all phrase that would need to be specified to not include illegals because they are subject to the jurisdiction of the US. You cannot change the wording without an amendment.