Once again the constitutional status of LGBT Americans rests in the hands of a 78-year-old moderate Republican, who returned from Harvard Law School to his hometown of Sacramento and remained there for 26 years—first as a lawyer and later as a judge—until Ronald Reagan made him a justice of the Supreme Court. After two and a half hours of oral arguments that were at turns inspired, clever and by the end tedious, the question of whether same-sex couples have a constitutional right to marry in every state will be decided by Justice Anthony Kennedy, just as he was the deciding vote in striking down a federal “Defense of Marriage Act” and state laws that criminalized gay sex.

Justice Kennedy knows this. The other eight justices know it. The 40-plus lawyers for the parties know it. The lawyers who wrote the record-high number of amicus briefs know it. It was the reality at the beginning of the argument and it remained the reality at the end. So what can we learn from what happened at the argument?

Reading Justice Kennedy. To those who are discomfited by having what is in effect a one-justice Court on this issue, it may come as some consolation that Justice Kennedy is anything but flip on the questions presented. In the first few minutes of the argument, he told counsel for plaintiffs Mary Bonauto that “the word that keeps coming back to me is millennia.” With marriage having been limited for centuries to different-sex couples, he said, “it is difficult for the Court to say we know better.” And let’s face it—what he was really saying was, it is difficult for me to say I know better.

But resolving these seemingly intractable conflicts is what Supreme Court justices do, whether they want to or not. It seems pretty clear that none of the justices are thrilled that this question is before them this year, but now they (and really he) will have no choice but to reason a path through to a conclusion. By the end of the argument, Justice Kennedy was in full to-be-or-not-to-be mode, suggesting that, despite those millennia, society has “learned a lot” about the lives of LGBT Americans in recent years, including that many same-sex couples share the goals of establishing committed relationships and raising children.

And dignity! The two most recent of Justice Kennedy’s LGBT decisions have leaned heavily on a concept of equal dignity and the need for the Court to recognize the harm generated by laws that demean or disrespect gay people. So, no surprise: both Bonauto and Solicitor General Donald Verrilli, who argued as the voice of the Obama administration for the right to marry, made frequent use of terms like “dignity, “second class status,” and “stigma.”

What was genuinely surprising, and a gutsy gamble, came from the lawyer defending Michigan’s ban of same-sex marriage. John Bursch argued that the state has no interest in using marriage as a means to bestow dignity on adult partners. Same-sex partners, he said, are entitled to the same dignity as different-sex couples, a principle that he proclaimed Michigan endorses. The state’s legitimate reason to exclude them from marriage, he said, was solely to create a structure that is most effectively designed to maximize the likelihood that biological parents will marry.

The gamble, while brave, may well backfire. Justice Kennedy immediately took umbrage, saying that he thought that it was clear that dignifying relationships was the purpose of marriage. And the argument did nothing to assuage the relentless questions from the four liberal justices questioning the logic of a link between excluding same-sex couples from marriage and benefiting other families. It was Bursch’s best shot at neutering the equal-dignity claim repeated by the plaintiffs, while still arguably prioritizing children. But the odds that this tactic will upset the dignity/status/stigma calculus that Justice Kennedy likely had in mind when the argument began are long.

Is Chief Justice Roberts in play? Much chatter among the lawyers in this field has centered on whether Chief Justice Roberts might surprise conservatives as he did in the healthcare reform case, and make it a 6-3 rather than 5-4 majority for requiring that states allow same-sex couples to marry. Maybe, but I doubt it. The chief’s dissent in Windsor (the DOMA case two years ago) emphasized his belief that the states should have leeway to set their own, differing definitions of marriage. His questions at oral argument, like those of Justice Kennedy, raised some tough points for both sides. But his only probing of the defendant’s position was to ask why the exclusion of gay couples from marriage did not amount to sex discrimination, and I find it difficult to believe that he will in the end go down that path.

To the plaintiffs, Chief Justice Roberts pushed on how polygamous marriages could be distinguished (the reply: the right to marry may attach to a threesome, but the state has a different set of interests in limiting such administrative headaches as adjudicating contested inheritance rights) and on why the plaintiffs should not wait to see how the political process plays out. “If you prevail,” he told Bonauto, “there will be no more debate.”

The chief also elevated the issue of religious objections. Justice Scalia persisted in suggesting to Bonauto that clergy members could be forced to marry same-sex couples if the Court made it a constitutional right—a frivolous argument, given the unquestioned rights of clergy to, for example, decline to marry interfaith couples. Roberts returned to the same set of issues later, noting that “there are harder questions” than whether clergy would be unprotected. What about a religious college’s married-student housing? he asked. To which Justice Alito added, What about whether tax exemptions could be challenged on the grounds that a religious institution such as a college discriminated against LGBT students? Solicitor General Verrilli replied that such issues will be decided at the state level, as balances are struck between anti-discrimination statutes and the scope of religious exemptions for religious organizations. Verrilli was right: These issues do loom in the future, regardless of whether all states or only some states allow same-sex marriage.

In his tone, Chief Justice Roberts appears much less emotionally engaged in the LGBT issues than either Justices Alito or Scalia or, for that matter, Justice Kennedy or the four liberal justices. (Justice Thomas was, as always, silent throughout the argument.) But signs of an Obamacare-like move? One question about sex discrimination law is a thin reed for that forecast.

Will there be a split decision? The Court heard argument in two cases: the first centered on whether all states must issue marriage licenses; the second asked whether if they do not have to allow same-sex marriage, do they nonetheless have to recognize already-existing gay marriages of couples who relocate to their state. If the Court requires all states to issue licenses, the second question is moot. But the second question raises the possibility that the Court will allow each state to determine whom to license, but require all states to recognize lawful marriages from any other state as a principle of horizontal federalism.

After 90 minutes of argument on the first question, the energy level in the courtroom was waning. Chief Justice Roberts barely participated in this set of exchanges, though he did ask the state of Tennessee’s lawyer when was the last time the state had actually refused to recognize an out-of-state marriage. The answer—1970—certainly suggested that the intensity of the state’s interest in deviating from the custom of mutual recognition was less than urgent.

I can easily see Chief Justice Roberts upholding state bans on same-sex marriage while ruling that those states must recognize same-sex marriage licenses from other states. The biggest problem with the split outcome possibility is, again, Justice Kennedy. Without his vote to deny relief on the broader first question, the Court never reaches the second question. It all rides on him.

How might the conservative wing of the Court try to win even if they lose? The clearest signal from oral argument was not who would win but how the conservatives plan to frame a loss. The message was not subtle. The drumbeat of alarm from Chief Justice Roberts and Justices Scalia and Alito about the consequences of nationwide same-sex marriage for religious groups might as well have come from the working draft of a dissent.

It is not uncommon for justices to send political messages in their opinions, especially dissents. Justice Ginsburg has openly called on Congress to revise the language of statutes such as the Voting Rights Act to effectively reinstate their most stringent provisions after a Court decision interpreted the text in ways that truncate the statute’s impact. Justice Scalia’s dissent in Lawrence v. Texas was a classic of the genre. Lawrence was the sodomy case, in which the Court’s majority struck down a law criminalizing gay sex. Justice Scalia’s dissent warned that there was a slippery slope from the majority’s reasoning about criminal laws to the recognition of a constitutional right to marry. Literally overnight, conservative commentary shifted from condemnation of the decision for its decriminalization effect to its possible future role in marriage debates, a move that increased exponentially when the highest state court of Massachusetts inaugurated gay marriage in the United States less than five months later.

If the Court finds that all states must allow same-sex couples to marry, the dissent will raise every possible problem for conservative religious faiths that surfaced during oral argument, and then some. Solicitor General Verrilli was spot-on in his response that these issues are both real and inevitable, regardless of how the Court rules in this case. Put another way, the immediate future of the marriage debate lies in neither constitutional law nor family law but in the messy processes of state legislative debates about the scope of accommodation when religious groups object to compliance with laws of general application. Social conservatives are gearing up to try to win that round in the culture wars.

Realistically, what is the best-case scenario for advocates of marriage equality? First, consider who might write the opinion. If Chief Justice Roberts does switch sides, his position as chief allows him to assign a justice to write for the majority. He could assign it to Justice Kennedy, but he could also assign it to himself. Many LGBT rights advocates would prefer to win by a less resounding 5-4 result to a 6-3 opinion written by Roberts, who almost certainly would aim for the narrowest possible grounding of a right to marry.

Assuming that Justice Kennedy writes, because he would be the senior justice if Roberts is not in the majority, there is no sign from oral argument that the next iteration of Kennedy jurisprudence on LGBT issues will clarify the doctrinal muddiness of past decisions. Will the reasoning be based on equal protection or the liberty-grounded right to marry? Most likely it will be a cocktail of equality and liberty principles, another step in the evolution of an equal-liberty philosophy. That’s fine. In fact, it’s probably better than judges’ having to make an arid choice between what are mutually reinforcing ideas. But Justice Kennedy’s articulations of the equal-liberty blend are sufficiently idiosyncratic that lower federal-court judges and advocates have a very thin trail of breadcrumbs to follow in reasoning out the different applications that will arise in future cases.

Will the Court find that sexual orientation classifications must be accorded some form of heightened scrutiny, as applies to classifications based on race, sex, national origin, or religion? Almost certainly not. Nearly all the questions from the bench—and all from Justice Kennedy—were framed as whether the right to marry covers same-sex couples, not whether anti-gay laws more generally are suspect.

And then there’s that other possibility… What about the worst case scenario? If Justice Kennedy swings back the other way to rule that there is no nationwide constitutional right to marry, I think that there is a decent chance that states will nonetheless be required to recognize same-sex marriages from other states. But what about the truly worst-case scenario: losing on both questions before the Court?

That outcome would parallel the Court’s 1986 decision upholding state sodomy laws, reversed 17 years later. Those 17 years, which also encompassed the era of greatest public debate over HIV/AIDS and gays in the military, transformed LGBT rights into a major national political and legal issue, gaining salience and seriousness after a defeat in the courts.

If today’s Court rejects a claim to marriage equality, the Justices know that the issue will return. Yes, five of them may choose to wait and see, as the states implored them to do. But in at least 17 states, with more than 40 percent of the nation’s population, the right of same-sex couples to marry is settled under state law. Those states are not going back. The result is that roughly 700,000 LGBT Americans are already married. They are not going to evaporate either.

A lot of Tuesday’s argument focused on whether states have a rational basis to believe that barring same-sex marriage actually serves any legitimate public interest. When the dust settles from the argument and the justices confer this Friday, the real issue is whether a majority will find that it is rational to prolong the process of whatever adjustments American law and society will have to make to a new social reality. History suggests not.