On that subject, it's really important for me to begin by saying that the separation of religion and public policy is important not only to keep faith from controlling a secular society, but (in my opinion, more importantly) to keep politics from muddying an otherwise holy Church.
That said, the only virtue left for the American nation is freedom. We ought to be free from unreasonable external hardship and free to exercise our will in a reasonable manner. And that's it! If you accept what I say here, we can only quibble with what "reasonable" and "unreasonable" mean.
TAXES
I think it is unreasonable to be taxed according to what you have accomplished in a greater degree than according to what you desire. As a matter of principle, I think sales tax and related taxes are much more fair than income taxes. Pragmatically, it's true that sales tax provides motivation to buy less while income tax does not provide incentive to earn less; however, what we've learned from this economic crisis is that it's in the national interest to provide incentive for reasonable, moderate spending by individuals and corporations. I think a sales tax does just that. I support a federal sales tax that, gradually over the course of a presidential term, rises to a level such that the income tax can be reduced by 75% or more. This may mean a federal sales tax of 7% or greater, but think about it: this also encourages reusing and reselling items we'd otherwise throw away, in order to avoid the tax! Very green. This would also save a lot of money and stress by reducing the manpower of the IRS and other related fields.
GAY MARRIAGE
I think every state should legalize gay marriage. Insofar as we ought to aspire to totally separate religion-specific values from public-interest values, we ought to drop resistance to gay marriage because almost all valid objections really boil down to religion-specific ones. I myself don't compare the battle for gay rights to the Civil Rights Movement of the mid-20th century; however, I think the freedom for gays to marry one another (in the secular use of "marriage") outweighs the freedom from public approval of perceived sin that some religious people would like to exercise.
ABORTION
I think there are effective arguments against abortion that have nothing to do with anything religious. Here's mine. Human beings have the right to freedom from undue interference with their bodies. Human beings have the right to freedom from the deprivation of their lives. Now there is a chance that fetuses are human beings. If they are not, then the two rights listed above do not contradict one another in an abortion, and so abortion ought to be legal, all else being equal. But if fetuses are human beings, then the two rights are at loggerheads and we must weigh which is more important--and, as most people would say, the right of a person to her life is of greater value than the right of a person's body from undue interference, all else being equal.
So the question is in the probability that a fetus is a baby. If it's 50/50, I say we ought not to allow abortions. If there is a one percent chance that fetuses are human, then that still ought to give us pause before we condone abortion. So on that basis, I am pro-life.
As an aside, I feel that there is very little good argument against abortion in my faith tradition (United Methodist). The Bible is fairly devoid of condemnations of abortion, as is the Book of Discipline.
ENTITLEMENT PROGRAMS
I think welfare is a worthy pursuit when it frees people from unreasonable external difficulty in achieving their goals. When it is anything else, it risks becoming an infringement on taxpayers' freedom from unnecessary taxation. The key to figuring out how many people should receive government welfare money, and for what purpose, and how much, and so on, is determining how much unreasonable external difficulty the government has a duty to keep from its citizens. I think we ought to give federal money to orphans in a great degree; the same for the mentally handicapped; the same for the physically handicapped, given that their handicap came from a situation not of their choosing; the same for the recently jobless; the same for the unemployable. Healthcare should be universal for children. I hesitate to give money to corporations and to the elderly simply because they are above a certain age. If they are too old to work, that is another matter. Of course we live in an age in which most people over 65 have planned on Social Security for their retirement, and to end it could be disastrous. But I think we should phase Social Security out in such a way that people my age stop paying for it, and as a result we see no benefit from it when we're older. That just seems to make sense.
FOREIGN POLICY
I think we should open Cuba up immediately. We should never conduct policy overseas or make war on the basis of ideological difference. War should be for the defense of American lives first, then the defense of innocent lives overseas, then the defense of American interests--in that order. No military action should be allowed except by its explicit passage by both houses of Congress, and never just the President's prerogative. We should pursue the protection of American companies with very low corporate taxes, not high tariffs. Globalization helps America most of all.
ENVIRONMENT
This is of great national and global interest. I believe strongly in federal funding and political capital expenditure for ever expanded environmental programs. Most environmental damage comes from concentrated sources: suburban yards use poison to grow grass, coal plants for Purdue University, and so on. Energy should be greatly diffused such that individual needs are dealt with on an individual basis. Instead of coal or nuclear power plants, install solar panels and wind turbines in most homes. Plant different grass in your yard so you don't give it fertilizer and then mow it three times a week. And my biggest focus in environmental thinking is the preservation of wild land. The government should greatly restrict the amount of land to which logging companies are privy on federal parks. This would drive up the price of paper and lumber and, in a very real way, force our hand in developing better sources for paper and building material. The preservation of wild lands, especially wooded places, is of the utmost importance to keep endangered species from extinction, to maintain places for human recreation, and to provide limited areas for human exploitation.
So that's what I think about some big issues. It feels good to get it out there!