Hillary Clinton's speech was competent, but she's stuck in a battle over which candidate is disliked less

It has been said a thousand times, but it bears repetition. This has been a historic week in the US. For the first time, a woman has become the presidential nominee of a major party. For the first time, the spouse of a former president is bidding to follow him into the Oval Office. And, on Thursday night, Hillary Clinton rose to the occasion.

Everyone knew she lacked the oratorical skills of her husband, or of Barack Obama, even of Joe Biden, the Vice-President. But she gave a very decent acceptance speech. It rarely soared, but it was crisp and punchy. She demonstrated how qualified she is for the job, and she lifted the veil a little on the most famous woman in America whom Americans don’t really know.

She made exactly the right noises to supporters of her primary rival Bernie Sanders, whose support is vital if she is to defeat Donald Trump in November. She reached out to the angry white males who are the bedrock of the Manhattan billionaire’s support. She projected competence, and exuded optimism over the country’s future.

She explained her unglamorous preference for policy over the theatrics of politics: “I sweat the details,” Ms Clinton admitted. And in this bizarre election year, when the theatrics usually rule, it’s as well someone is bothering about details. In short, she did what she had to do. But will it make any difference?

By the normal standards of US party conventions, this Democratic one was brilliantly orchestrated, and far superior to the gloom-laden and cack-handed Republican gathering of the week before. Apart from a wobble on the first day, the Sanders dissent was deftly handled – thanks in good measure to the statesmanship of the Vermont senator himself, who spelled out to his diehard supporters that all else paled beside keeping Mr Trump out of the White House.

Gleefully, the Democrats hijacked their opponents’ traditional themes of patriotism and national security. By its end, the convention was a glittering showcase for party unity, and a celebration of American diversity. But again, will it make any difference?

For all its shortcomings, Mr Trump received a noticeable “bump” from his convention, and that has given him a narrow lead over Ms Clinton in some polls. By any reasonable yardstick, she should achieve a larger one from hers. But in 2016 the old orthodoxies don’t count. Right now, the signs are that this will be a close election, that may boil down to which of two unpopular candidates Americans dislike less.

Seen from that perspective she faces considerable hurdles. First, there’s the “third-term problem". After a party has held presidential power eight years, Americans tend to vote the other one into office (the only recent exception was the 1988 victory of George HW Bush after two terms of Ronald Reagan).

Americans crave change, and the whole convention was geared to portray Ms Clinton as a change-maker. But she’s been a leading figure on the national stage for a quarter century, the personification of an establishment that voters, and Trump voters in particular, detest. Clinton-style incrementalism is boring compared to a newcomer’s flamboyant promises of instant change.

The oddity about Ms Clinton is that she’s very popular when she’s not running for office – when she’s a working senator, or Secretary of State. But the moment she takes the campaign trail, her ratings, especially for honesty and trustworthiness, plunge. The row over her State Department emails has only strengthened these impressions.

This is the challenge Hillary Clinton must overcome, if she is to make the biggest mark on history of all, by winning on 8 November.