In the wake of the Newtown tragedy, President Obama said "if there is a step we can take that will save even one child" we should take it.
President Obama should explain directly to the American people why this principle applies to guns, which kill (murder, accident, or suicide) over 1,000 children each year, but not to abortions which kill (intentionally) over 1,000,000 children each year.
President Obama's response could also bear in mind that gun ownership is directly protected by the second amendment to the Constitution ("shall not be infringed"), while abortions are protected only by Supreme Court ruling, based on a right to privacy which is no where enumerated in the Constitution.