Donald Trump had a big job to do Thursday night, but of course big jobs are what he does for a living — so it’s really no surprise that he got it done . . . beautifully.

The Republican nominee needed to not just act presidential, but be presidential — while still being himself.

He needed to keep every ounce of New York toughness and roughness he’d shown in the campaign to date, while also showing sensitivity and a sincere commitment to making life better for all Americans.

He needed to show a coherent policy vision recognizably his, that spoke to “his” voters, regular Republicans and all Americans.

And he did it in a speech characteristically Trump — wandering and emphatic, hard-hitting and a little chatty; blending policy and principle, anecdote and attack line, while speaking from the heart.

The Republican nominee, citing Orlando, vowed to protect LGBTQ citizens and got cheered by the convention hall.

He talked tough on law and order — while vowing to ask himself, with every action he takes, “Does this make life better for young Americans in Baltimore, Chicago, Detroit, Ferguson who have as much of a right to live out their dreams as any other child in America?”

And: “Nothing has affected me more deeply than the time I have spent with the mothers and fathers who have lost their children to violence spilling across our borders.”

That is, he rooted his trademark issues — trade as well as immigration reform; America First and the “rigged system” that serves the elites — in human reality, human concerns.

From time to time, he slammed Hillary Clinton — the epitome of that rigged system, collecting billions from the special interests behind it — for her scandals and her crimes, but above all for her “message that things will never change.”

If you want the politically correct line, the “corporate spin, the carefully crafted lies” — tune in to the Democratic convention.

Above all, he hit her for her campaign’s line, “I’m with her.” Once again, he pledged, “I am with you — the American people. I am your voice.”

That echoed a line from much earlier on: “I have joined the political arena so that the powerful can no longer beat up on the people that cannot defend themselves.”

The point echoed throughout — from his guarantee to bring jobs “roaring back into our country . . . fast” to his promise that “we will be a country of generosity and warmth” but also “of law and order” to his vow to “rescue kids from failing schools by helping their parents send them to a safe school of their choice.”

He made shout-outs on specifics — judicial nominees like Antonin Scalia, “repeal and replace disastrous ObamaCare,” real reform to take care of veterans, “defeat the barbarians of ISIS” — and it all fell together as well as it can in any political speech.

He ad-libbed plenty — most tellingly, in saying “I’m not sure I really deserve it” when acknowledging the support he’d received from Evangelicals.

Donald Trump showed a hint of humility there, as he did when talking of his kids, his dad and his mom.

And he connected his story of the last year with his promises: “Remember, all of the people telling you that you can’t have the country you want are the same people” who told you that Trump could never make it to this point.