The Bishops' document Forming Consciences for Faithful Citizenship identifies several such issues. Foremost among them are the life issues: abortion and infanticide, euthanasia, embryonic stem-cell research, human cloning. Another is the protection of marriage as the union of one man and one woman.
We must evaluate every candidate's positions on these issues. Frankly, I find Obama's record and positions on life issues, marriage, and parental rights disturbing. His stances on these issues are extreme, to put it simply. For example:
Obama is a firm supporter of legal abortion, consistently earning 100% scores from NARAL. He has reiterated his support for abortion many times, including in his statement to NARAL: "I have consistently advocated for reproductive choice and will make preserving women's rights under Roe v. Wade a priority as President. I oppose any constitutional amendment to overturn the Supreme Court's ruling in this case."
In line with his beliefs, he is a co-sponsor of FOCA, the "Freedom of Choice Act," which goes even beyond the Roe and Doe decisions to nullify virtually all federal and state limitations on abortion. It would make taxpayer-funded abortion on demand throughout all nine months of pregnancy into a fundamental right. Nearly all the pro-life achievements in legislation at both the state and federal levels, such as women's right to know laws (informed consent), parental notification, and even the ban on partial birth abortions would be reversed. Even the right of medical personnel and hospitals (such as Catholic hospitals) to decline to provide abortions due to conscientious objections would be denied by this law.
When the Supreme Court upheld the ban on partial-birth abortions, Obama opposed that decision.
Planned Parenthood's political action arm has endorsed him based on his record and his pledge that "the first thing I'd do as president is sign the Freedom of Choice Act."
(Update: also see What's at stake in this election, in Barack Obama's own words)
II. Embryonic stem cell research
Obama has consistently voted in favor of embryonic stem cell research, even saying that, "Embryonic stem cells can be obtained from a number of sources including in vitro fertilization. ... We should expand and accelerate research using these embryos."
III. Human cloning. Actually, this contains two intrinsic evils - the first in the creation of the clone for research, and the second in the destruction of the new human life once it has served its purpose.
He co-sponsored a bill that would allow the cloning of human embryos for research purposes, but require that they then be killed.
When Tim Russert asked Obama and Clinton if “there are any words or votes that you’d like to take back ... in your careers in public service,” Obama answered that it was a "mistake" to have joined the Senate in the unanimous consent on the Terri Schindler-Schiavo case. This consent provided her family with a last opportunity to try to save her. In other words, Obama singled out his agreement in a last-ditch attempt to prevent the starvation death of a severely disabled woman as the mistake of his public career.
Just to clarify, a lot has been reported in the media about Terri's case. There were many claims that she was in a "persistent vegetative" state as well as counter-claims that she was responsive to people and things around her. Yet this was irrelevant. She was not dying from any underlying condition. She was not on any life-support machines. It is a little-known fact that 29 disability-rights organizations filed legal briefs and lobbied Congress to make them understand that this was not about a "right to die" but about protecting her right to continue living. All she needed was food and water, just like the rest of us.
As Pope John Paul said:
Just because the chances of recovery are judged small and waning, when the ‘vegetative’ state lasts more than a year, does not justify withdrawing minimal care for the patient, including nutrition and hydration. Death by starvation or thirst is, in fact, the only possible outcome of such a withdrawal. If done knowingly and willingly, this ends up being euthanasia by omission.This teaching has since been confirmed by the CDF with Pope Benedict's approval.
The sick person in a ‘vegetative’ state, awaiting recovery or a natural end, still has the right to basic health care (nutrition, hydration, cleanliness, warmth, etc), and to the prevention of complications related to his confinement to bed. He also has the right to appropriate rehabilitative care and to be monitored for clinical signs of eventual recovery.
I want particularly to emphasize that the administration of water and food, even when provided by artificial means, always represents a natural means of preserving life, not a medical act. Its use should be considered, in principle, ordinary and proportionate, and thus morally obligatory, insofar as and until it attains its proper goal of nourishing the patient and alleviating his suffering." (John Paul II, Address on Life-Sustaining Treatment and the ‘Vegetative’ State §4)
V. Marriage. Not a direct life issue, but equating homosexual unions to marriage is again intrinsically evil.
"Society owes its continued survival to the family, founded on marriage. The inevitable consequence of legal recognition of homosexual unions would be the redefinition of marriage, which would become, in its legal status, an institution devoid of essential reference to factors linked to heterosexuality; for example, procreation and raising children. If, from the legal standpoint, marriage between a man and a woman were to be considered just one possible form of marriage, the concept of marriage would undergo a radical transformation, with grave detriment to the common good. ... all Catholics are obliged to oppose the legal recognition of homosexual unions." (Considerations Regarding Proposals to Give Legal Recognition to Unions Between Homosexual Persons, CDF, approved by Pope John Paul II)
Obama has pledged to repeal the federal Defense of Marriage Act.
OK, so we are all used to pro-abortion politicians but this one shocked me. Are you familiar with the "Born Alive Infants Protection Act" (BAIPA) that was passed by Congress and signed into law by President Bush in 2002? This very simple law states that once a baby is born alive, even if it happens "accidentally" during an abortion, that baby is legally entitled to all the normal care than any baby is legally entitled to have. In other words, once born, the baby cannot be discriminated against, killed, or left to die in a utility closet simply because he or she is unwanted.
Initially, NARAL opposed the measure, but later dropped its opposition to avoid the political fallout. Indeed, this is such a common-sense measure that the US House passed it 380-15 and the Senate 98-0.
Obama was not a member of the US Senate at that time. But, when the Illinois senate considered a very similar measure, then-state senator Obama tried to prevent it's reaching the floor for a vote, argued against it on the Senate floor, and voted against its passage three times. You can read the text of the measure yourself, at the Illinois General Assembly website. It's very short and clear.
His position on this issue is nothing short of approving murder. Obvious and cold-blooded murder of the weakest, the most innocent, and the most defenseless.
Is that not disturbing?
Many people say that you cannot rule out a candidate on the basis of a single issue. Generally, I think they are right, but here's what our bishops said: "As Catholics we are not single-issue voters. A candidate’s position on a single issue is not sufficient to guarantee a voter’s support. Yet a candidate’s position on a single issue that involves an intrinsic evil, such as support for legal abortion or the promotion of racism, may legitimately lead a voter to disqualify a candidate from receiving support." (Faithful Citizenship, my emphasis)
If that is the case, then what about the candidate who supports a half-dozen intrinsic evils?