It’s fantasy football time in political punditry, as commentators try to dismiss Hillary Clinton’s dominance in the polls — yes, Clinton Derangement Syndrome is alive and well — by insisting that she would be losing badly if only the G.O.P. had nominated someone else. We will, of course, never know. But one thing we do know is that none of Donald Trump’s actual rivals for the nomination bore any resemblance to their imaginary candidate, a sensible, moderate conservative with good ideas.

Let’s not forget, for example, what Marco Rubio was doing in the memorized sentence he famously couldn’t stop repeating: namely, insinuating that President Obama is deliberately undermining America. It wasn’t all that different from Donald Trump’s claim that Mr. Obama founded ISIS. And let’s also not forget that Jeb Bush, the ultimate establishment candidate, began his campaign with the ludicrous assertion that his policies would double the American economy’s growth rate.

Which brings me to my main subject: Mrs. Clinton’s economic vision, which she summarized last week. It’s very much a center-left vision: incremental but fairly large increases in high-income tax rates, further tightening of financial regulation, further strengthening of the social safety net.

It’s also a vision notable for its lack of outlandish assumptions. Unlike just about everyone on the Republican side, she isn’t justifying her proposals with claims that they would cause a radical quickening of the U.S. economy. As the nonpartisan Tax Policy Center put it, she’s “a politician who would pay for what she promises.”