Former Secretary of State Hillary Rodham Clinton. (Manuel Balce Ceneta/AP)

Hillary Clinton looms over the Democratic Party like Evita from her balcony. She is the presumptive presidential nominee, the likely one, the inevitable one, the one and only, the one before all others run in awe and panic. Behold the biggest and, in a sense, only thing in the Democratic Party. All she lacks is a song.

In contrast, the GOP is like a preschool class before nap time: seemingly dozens of potential presidential candidates crawling all over each other. Some, such as Rick Santorum and Rick Perry, we have seen before. Others, such as Marco Rubio and Ted Cruz, have not yet run for president, but they probably will. So might Rob Portman, John Kasich, Scott Walker and Mike Pence — solid Midwestern types all. And then there’s Paul Ryan, who was on the ticket last time, and Mike Huckabee, who has done this sort of thing in the past (won Iowa, remember?) and also Chris Christie and Rand Paul. It will be a banner season for political consultants.

Not mentioned yet — but here he comes — is Jeb Bush. His brother, the former president, put Jeb’s chances of running at “50-50.” Continuing in that vein, George W. told “Face the Nation” on Sunday that his brother “is not afraid to succeed” nor, he said a moment later, “is he afraid to fail.” He might be afraid of the impact that a campaign and the presidency could have on family life, but the former president said even all this can be overcome. Their father, George H.W., did it.

The prospect of another Clinton-Bush presidential race has to fill many Americans with dread. It’s not that either one is unacceptable. It’s rather that their candidacies will mean countless stories about political dynasties and why they are, for some reason, bad. We will hear comparisons to the Roosevelts, the Adamses, the Tafts, the Rockefellers, the Kennedys and even lesser dynasties such as the Cuomos of New York — Mario, the father, Andrew, the son, and, had Andrew stayed married to Kerry Kennedy, just about every office in the land.

Dynastic politics has, in effect, become the American way. Udalls run in the West, Carters and Nunns in Georgia, a Brown is inevitably the governor of California and a Daley mayor of Chicago, just not at this moment. But none dominates their party as Hillary does the Democrats. You could see her as the consequence of dynastic politics — her husband was the president, after all — but right now her dominance is more a product of what has happened to the Democrats than anything she has done as a politician. As my colleague Dan Balz has pointed out, the past two midterm elections have done to the Democratic Party what World War I did to the French political elite — decimated it. What was lost was not just individual races but the future. Republicans will now control 23 states — the governorship and the legislature — while the Democrats will have just seven. States, in the coinage of Justice Louis Brandeis, are the laboratories of democracy. They’re where both interesting ideas and personalities often come from.

I have grave doubts about Hillary Clinton’s viability. She still has no resounding message, and in an anti-Washington era she is the very personification of the loathed capital city. Her credentials, her experience, her marriage to Bill and her association with President Obama will be used against her. By many measures, she may be the best candidate, but this is a country that punished George W. Bush for an unnecessary war by inexplicably electing him to a second term. He was, as they say, likable.

At this point in the election cycle of 2008, Obama was a very junior senator from Illinois. By the end of that year, he was the president-elect. We are in a dizzying era of dizzying change. The United States is now at war with the Islamic State, which seemed to come out of nowhere. Netflix, Amazon and the smartphone were mere rumors, it seems, just yesterday. We are psyched on the juice of change. Somehow Clinton needs to embody that zeitgeist — to be an insider with an outsider’s revulsion for what she’s seen.

It’s not possible that Clinton is actually mulling over whether to run. Not only does she have a moral obligation to do so — she’s repressing other potential candidacies and vacuuming up their funds — but the sooner she drops the standard political pose and exudes genuine feelings, the better a candidate she will be. She is not the Democratic Party’s best hope. She is its only hope.

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