“It would be much better if Congress drafted and passed an amendment which clearly defines who becomes a citizen when born in the U.S.”
That would be the right way to do it, which pretty much guarantees that it won’t be done at this time. We’ll chase our tails hoping for a landmark Supreme Court decision which won’t happen and which was already partially addressed in United States v. Wong Kim Ark (1898).
Too many forget that the 14th Amendment did not just make slaves citizens, it also made citizens of the thousands of native born children of Irish, German and others who had immigrated to the US during the Civil War years. Previous to the early 1890’s anybody could come here with no questions asked and they became defacto citizens. During the Civil War, no differentiation was made between natural born soldiers or foreign born soldiers in the Union Army when the election of 1864 took place.
It was not until the massive immigration waves of the late 1880’s that immigrants became subject to scrutiny. Part of the Wong Kim Ark supportive argument was that ending birthright citizenship would affect hundreds of thousands of European immigrants children who had been born here.