2008 was destined to be a Democratic year at the presidential level. As has been pointed out in many other places, the electorate was thoroughly tired of George W. Bush and after the economic crisis that began with the failure of the Lehman Brothers Bank on September 14, last year's election would have been an unwinnable scenario by any Republican candidate against any competent Democrat (maybe if the Democrats had nominated John Edwards and the Rielle Hunter scandal had erupted a week before the election, but it would have taken something of that magnitude to shift the poltical landscape last year enough to produce a GOP win.)
In that framework, it is worth taking a look back to last year's epic primary battle betwen Barack Obama and Hillary Clinton. There is no reason to suppose that the November result would have differed much (Clinton might have lost North Carolina and Indiana and won Arkansas, West Virginia, and/or Missouri but regardless of small differences in the electoral map, in the end the result would have been the same.)
The differences come after that. The ongoing differences between Clinton and Obama are highlighted by a report today that Clinton urged Obama to take a tougher line last week with Iran. One can argue whether she was right or not (certainly the Khameini/Ahmadinejad regime has blood on their hands and deserve to be called on it, but equally certainly the unarmed demonstrators never had a chance against the armed militia, backed by the police, backed by the army if it had come to that, and Obama was fundamentally right during the campaign that Iran is too big and too important a country to maintain the Bush policy of isolation in regard to) but this is only the tip of the iceberg in terms of what is different. Hillary Clinton remember, backed the Iraq war (and continued to back it well after most Democrats had realized that the most we could win was a Pyrrhic victory) even siding with the Bush White House on the surge, interrogation methods and a whole host of other war issues, and also voting with the Bush White House against Iran on a resolution in late 2007 naming the Revolutionary Guards as a terrorist organization (a vote which in fact may have cost her crucial support in Iowa, especially when she appeared to blow off voter anger over it, chastizing a man who asked her about it at a rally.)
It is impossible to know how Hillary Clinton as president would have dealt with any specific situation but let's remember that she was intimately involved in decision making during her husband's presidency and he would have been very involved in hers. Hillary is not Bill, but the Bill Clinton presidency (not least because they do in fact have similar political views) provides a guideline for what we might have expected. Bill was far more ready to use military force than Obama has been. For example it's a good bet that if Hillary Clinton were president we'd have marines on the ground right now returning president Zelaya to Honduras (remember that Bill Clinton faced a nearly identical situation in Haiti and sent the marines to restore Aristide.) It's also worth noting that Hillary Clinton in the Senate several times voted for more funding for the military (including for the war in Iraq) that Barack Obama opposed.
Besides the fact that Bill (and very probably Hillary) was and would have been more hawkish in terms of foreign policy, there are also domestic policy differences.
On social issues there are very few differences. It's not hard to imagine Hillary Clinton nominating Sonia Sotomayor to the Supreme Court, and on issues like the Ledbetter Fair Pay Act and the 'Mexico City Rule' the results would likely have been identical. In fact, arguably Hillary Clinton would have done more on gay issues than Obama has done (an area of civil rights where he has been slow to implement promises he made during the campaign.)
However on economics there are some major differences. Hillary Clinton was strongly pushed by the DLC (Democratic Leadership Council), an economically conservative pro-business group within the Democratic party. Bill Clinton was instrumental in its founding, and if one thinks back to the Clinton Presidency on economic issues Bill Clinton had a decidedly conservative tilt. He actively pushed for less regulation of markets. On this issue he was nearly indistinguishable from most Republicans; in fact, Bill Clinton deserves a share of the blame for the present multiple crises caused by lack of adequate regulation. For that matter Hillary would likely have had more trouble than Obama reversing course on regulation, not only because doing so would cut against her core economic beliefs but because in many cases Obama has had to change rules that were written during the Bill Clinton presidency-- something Hillary Clinton would certainly have to answer about. Also, Bill Clinton generally was opposed to bailouts and favored free trade. Hillary Clinton in the Senate took these positions as well. There may have been a stimulus bill if Hillary Clinton were president but with the Clintons' aversion to deficits (even going back to Arkansas) and her early campaign promise (granted, made before all hell broke loose) to produce balanced budgets it might not have been large enough. Remember too that Al Gore was frustrated that the Clinton White House never pushed for higher CAFE standards or other environmental legislation because they spent too much time listening to the business lobby, and it's likely that if Hillary Clinton were president we would never have seen much of an effort along the lines of the global warming bill the House passed last week.
On health care, Hillary's most famous battle (and most famous defeat) came in 1994 trying to create a universal coverage plan. During the primary she promised to try again, but between her dislike of deficit spending (one reason for the big surpluses during the Clinton presidency was that they raised taxes to pay for a health care plan early on but then didn't get the plan) and her more cautious approach (even more so having been burned once on it) the likelihood is that healthcare 'reform' would have been something much more modest than the sweeping changes we are likely to see in the Obama bill. With the Clinton ideal of focus groups, triangulation and pollwatching driving the process we might well end up with a fancy sounding 'reform' that in the end would do relatively little. There might have been a mandate to buy health insurance (as there is today in Massachusetts) but no public plan to hold down costs by competing with the private plans.
Of course, there are areas where I don't agree with Barack Obama (and at least in one area, civil rights, there are reasons to believe that Hillary Clinton might have been the more progressive of the two) but on balance I believe that it is a good thing that Democratic activists (including me) became involved in the primary and pushed Obama over the finish line. In at least two major areas, foreign policy and economic policy it is clear that because of the primary we have a far more progressive presidency than we would have if Hillary Clinton had been nominated.