Hypotheticals are dangerous things. Suppose you're a presidential candidate, for example. A hypothetical could force you to take a position on something you'd rather not talk about, and just when you least expect it.

That's just speaking hypothetically, of course.

"Rewriting history is hypothetical," former Florida governor Jeb Bush (R) said Wednesday in Reno, when asked about the war in Iraq. "If we're gonna get back into hypotheticals I think it does a disservice for a lot of people that sacrificed a lot."

On Thursday, he answered the question anyway:

If we're all supposed to answer hypothetical questions: "Knowing what we now know, what would you have done?" I would not have engaged. I would not have gone into Iraq.

In Reno, he had said "the focus" should be "on the future." The future, though, is hypothetical by nature. There's a lot we don't know about it. Indeed, Bush might not even run for president, as he's insisted again and again.

"I'm running for president in 2016," Bush said in Reno, but just as a way of raising the possibility.

"The focus is going to be about how we, if I run, how do you create high sustained economic growth?" he went on to say.

Scott Sonner and Thomas Beaumont explained the significance of that "if" for the Associated Press:

The caveat is important. It’s one Bush has uttered countless times since January, traveling to early-voting and battleground states and meeting voters. It’s what has allowed him to raise limitless money to fuel a super PAC expected to complement his campaign once he officially announces his candidacy.
Bush’s team had nothing to say about his slip.

Yet when you're traveling the country, talking to voters in town halls and raising tens of millions of dollars, that hypothetical campaign you keep talking about starts to look more and more like an actual campaign. And under the law, simply saying that you're not running for president doesn't give you a break from the rules if you actually are running.

Here's another hypothetical: What if Bush acknowledged he was running for president, and then went on to ignore the rules on fundraising and coordination, without making any pretense about it? The Federal Election Commission might not be able to do anything about it. Its members are always evenly split on party lines and largely unable to enforce the law, which is why the chairwoman recently called the agency "worse than dysfunctional" in an interview with Eric Lichtblau of The New York Times.

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What's in Wonkbook: 1) Bush's Iraq War comments 2) Opinions, including Matthews, Smith and Ignatius on free trade 3) Why female Hill aides can't spend time alone with their bosses, and more.

Chart of the day: Median global income doubled over the past decade, and the distribution of income also became more equal. By 2035, according to one projection, median income will have doubled again worldwide, with the fruits of the global economy becoming yet more evenly distributed. The Economist.

1. Top story: Bush says

Bush clarifies his stance on the war in Iraq. "'Knowing what we now know... I would have not engaged. I would not have gone into Iraq,' Bush said... For four straight days, he gave wavering, uncertain and incongruous answers to questions about the Iraq war as he struggled with whether and how much to differentiate himself from his older brother, former president George W. Bush. ... His position is at odds with the views of some of his foreign policy advisers, many of them veterans of his brother’s administration who remain some of the Iraq invasion’s staunchest defenders. ... Bush called for increasing U.S. presence in Iraq to help rid the country of the 'barbaric Islamic threat.' He told reporters, 'I think we need to reengage and do it in a more forceful way.' " Philip Rucker and Ed O'Keefe in The Washington Post.

That was the only direct statement he'd made on the question all week. "Bush’s trouble began when anchor Megyn Kelly asked him the most obvious of questions about his brother’s scarred Iraq legacy: 'Knowing what we know, would you have authorized the invasion?' 'I would have,' Bush said. ... Bush said on the radio that afternoon that he had, in fact, misunderstood Kelly. But when host Sean Hannity asked it again, Bush said, 'I don’t know.' He called the query a 'hypothetical.' That only further emboldened his critics, who pointed out that most of a presidential campaign (or soon-to-be campaign, in Bush’s case) involves discussing hypotheticals. By the time Bush arrived in Nevada on Wednesday, he was repeatedly getting asked about Iraq." Patricia Mazzei in the Miami Herald.

Primary source: The transcripts of everything Bush said about Iraq this week. Philip Bump in The Washington Post.

KRUGMAN: Bush is refusing to learn from the past. "Mr. Bush resorted to the old passive-voice dodge, admitting only that 'mistakes were made.' Indeed. By whom? Well, earlier this year Mr. Bush released a list of his chief advisers on foreign policy, and it was a who’s-who of mistake-makers, people who played essential roles in the Iraq disaster and other debacles. Seriously, consider that list, which includes such luminaries as Paul Wolfowitz, who insisted that we would be welcomed as liberators and that the war would cost almost nothing... But refusal to learn from experience, combined with a version of political correctness in which you’re only acceptable if you have been wrong about crucial issues, is pervasive in the modern Republican Party." The New York Times.

2. Top opinions 

MATTHEWS: Opponents of free trade put the American middle class before the world's poor. "A true anti-poverty trade agenda would... put US workers in competition with more — and poorer — workers abroad. The effects on US workers would likely be small, but even if they weren't, that trade is worth making. Fighting desperate poverty in the developing world is more important than marginally boosting the US middle class. And there are many, many ways to help the American middle class that don't involve keeping the world's poorest people in a state of total immiseration." Vox.

NOAH SMITH: Unlike past trade agreements, the Pacific deal won't lower U.S. wages. "It’s mostly about trade with Japan and South Korea, which has asked to join the pact. These are rich countries, with tons of capital and very high labor costs. In fact, Japan’s labor costs are so high that Japanese auto manufacturers now build a lot of factories in the U.S. American workers are not going to lose out to the Japanese and South Koreans. ... The second reason TPP isn't like past trade deals is the intellectual property protection. ... Stronger international IP protection will help U.S. companies export more, which makes them hire more American workers, which increases the amount that those workers spend on the local economy. Yes, there are many problems with the U.S.’s intellectual property laws. But international harmonization of IP wouldn't exacerbate these problems." Bloomberg View.

IGNATIUS: Hillary Rodham Clinton must take a stand on trade. "What does Hillary Clinton believe about the Trans-Pacific Partnership or the Iran nuclear deal? You would assume that she’s supportive because she helped get both agreements started. But she has been a study in reticence — a trimmer checking the political winds, rather than a leader. ... Is Clinton really running so scared from Warren that she’s ready to disown economic policies she helped shape? Does she think that running against Obama’s economic record will be good politics? Clinton should put away the waffle iron. ... Her caution conveys the sense that she’s running because she wants to get elected, rather than as the exponent of a set of beliefs." The Washington Post.

MEYERSON: It's about time a democratic socialist, ran for president. "Bernie Sanders’s presidential campaign is the first such effort by a democratic socialist since Norman Thomas waged the last of his six such campaigns on the Socialist Party ticket in 1948. ... Historically, the role of the two great American socialist standard-bearers Eugene Debs and Thomas, and such socialist members of Congress as Meyer London and Ronald Dellums, was to advance ideas that their progressive compatriots were sometimes able to enact — partially — years or decades later, or that later were transformed into common sense. ... The independent from Vermont is not likely, putting it mildly, to displace Hillary Clinton as the Democratic front-runner... but in the best tradition of Debs and Thomas, he is advancing ideas that Democrats, Clinton included, may in time embrace." The Washington Post.

Blues interlude: B.B. King passed away Thursday at the age of 89. Tim Weiner in The New York Times.

Here's "The Thrill is Gone" from Completely Well (ABC, 1969).

3. In case you missed it

The Senate will consider moving ahead with Obama's trade agenda. "Just two days after Democrats defied Obama to block debate on a bill to 'fast-track' trade deals such as the Trans-Pacific Partnership (TPP) trade deal through Congress, the Senate voted 65 to 33 to move ahead with consideration of the measure. Strong support for the bill on this second go-round suggests senators are unlikely to reject the bill, although heated debate is still expected in the Senate over amendments and later in the House of Representatives, where many Democrats staunchly oppose the TPP on fears trade liberalization will cost U.S. jobs." Richard Cowan and Krista Hughes for Reuters.

Boehner blames speed, not a lack of funding, for the Amtrak derailment. "By Thursday, House Speaker John Boehner had had it with questions from Democrats – and reporters – about congressional funding for Amtrak and Tuesday’s deadly derailment of a Northeast Corridor passenger train in Philadelphia. 'Are you really going to ask that? That’s a stupid question,' Boehner told a reporter. ... Boehner, R-Ohio, said that the derailment wasn’t about money because the train with 238 passengers and five crew members aboard was traveling through a section of Northeast Philadelphia at over 100 miles per hour, double the regulated speed for that section of track. ... The House of Representatives’ Appropriations Committee voted Wednesday to cut Amtrak’s annual subsidy from $1.4 billion to $1.1 billion." William Douglas for McClatchy.

In fact, additional resources could have prevented the deadly wreck. "In 2008, Congress ordered the installation of what are known as positive train control systems, which can detect an out-of-control, speeding train and automatically slow it down. But because lawmakers failed to provide the railroads access to the wireless frequencies required to make the system work, Amtrak was forced to negotiate for airwaves owned by private companies that are often used in mobile broadband. ... The railroad struggled for four years to buy the rights to airwaves in the Northeast Corridor that would have allowed them to turn the system on. ... Despite the delays, the system may have been just months from being operational when Northeast Regional Train No. 188 careered into a sharp curve at over 100 miles per hour, twice the posted speed, and hurtled off the tracks Tuesday night." Michael D. Shear and Jad Mouawad in The New York Times.

Female congressional staff are often prevented from spending time alone with their their male bosses. "Several female aides reported that they have been barred from staffing their male bosses at evening events, driving alone with their congressman or senator, or even sitting down one-on-one in his office for fear that others would get the wrong impression. Follow-up interviews with other Hill aides make clear that these policies, while not prevalent, exist in multiple offices—and they may well run afoul of employment discrimination laws, experts say. Because of the sensitivity of the issue, and the fear of retribution, many of these women and some of their male counterparts spoke with National Journal on the condition of anonymity and declined to publicly name their bosses." Sarah Mimms in National Journal.