True. One has to assume in that context that by "life" is meant "a human being". Still, like most other observable phenomena, the process is a continuous one, without a sensible beginning. For pragmatic reasons the law favors sharp age cutoffs for many types of laws. Scientifically and morally, however, no sharp division along a continuum is well-justified. When it comes to driving age, no one much cares, but when it comes to life and death, mistaking pragmatic for moral reasoning can only lead to hostile, even violent, irreconcilable differences.
At any rate, the legal prohibitions of abortion in America before 1973 were not because the country was under the control of Catholic "articles of faith." No idea what Kerry is thinking of here. He is an oddball.
Apparently he thinks that any declaration the Church makes is suddenly taken out of any legitimate moral or political consideration. It makes me wish the Church would come out for higher taxes.
How anyone can consider Kerry a smart politician after making that calculated yet indefensible blunder is beyond me. But then, it's all about anyonebutbush, anyway.
These statements about the nature of human life or the human person which pop up in pro-abortion discourse are ontological propositions. Liberals tend to be rather underendowed (and underwhelming) in this area of cognitive exercise. All "science" involves a certain set of ontological presuppositions about the nature of reality.