Here are a few (but not all) of Republican presidential candidate Donald Trump's insults and interruptions during a brutal debate in St. Louis on Oct. 9. (Gillian Brockell/The Washington Post)

Donald Trump made it clear he was going to come out swinging at Hillary Clinton in Sunday night's debate. And he tried.

The problem was, he was pulling his punches.

And not because he meant to, mind you; it was largely because his attacks lacked coherence and apparently preparation. And, accordingly, they didn't land with much force.

From Bill Clinton's indiscretions to Syria policy to accusations that Clinton has run nasty campaigns and fomented the birther movement, his attacks were woefully short on details and conclusions, and each of them seemed to pass with a whimper — and without the need for a real Clinton response.

The most apparent example was the Bill Clinton attack. Trump telegraphed this one for days, saying he would respond to a Washington Post report of him talking in lewd and sexually aggressive terms about women in 2005 by turning the attack on Bill Clinton, and Hillary Clinton's role in enabling him — then bringing some of Bill Clinton's accusers to a surprise photo op roughly 90 minutes before the debate.

But he didn't really do it — not completely. He lodged half an attack, and it was over. He didn't even get into the idea that Hillary Clinton enabled her husband.

During the second presidential debate on Oct. 9, Republican presidential nominee Donald Trump accused former president Bill Clinton of abusing women. (The Washington Post)

Ditto his previewed attack on her legal defense of an accused child rapist in the mid-1970s. Trump noted that she defended the man, but he didn't really drive home the point that other Republicans have argued — that it's contrary to her pitching herself as a defender of women and her statements that women who accuse men of sexual assault should be believed.

Here's the brief attack:

If you look at Bill Clinton — far worse. Mine are words, and his was action. His was what he's done to women. There's never been anybody in the history of politics in this nation that's been so abusive to women. So you can say any way you want to say it, but Bill Clinton was abusive to women.

Hillary Clinton attacked those same women and attacked them viciously. Four of them here tonight. One of the women, who is a wonderful woman, at 12 years old, was raped at 12. Her client she represented got him off, and she's seen laughing on two separate occasions, laughing at the girl who was raped. Kathy Shelton, that young woman is here with us tonight.

Whether it's a good idea for Trump to go down this road is one thing. But he didn't even really explain the attack. Again, the idea that Bill Clinton abused women isn't really the attack. He's not running; Hillary Clinton is.

Similarly, his attack on Clinton's defense of Shelton's accuser doesn't mention the idea that Clinton questioned the then-girl's credibility. Republicans have argued that this is at odds with her comments that victims of sexual assault should be believed. Trump said none of that.

On the birther thing, Trump was a hodgepodge:

Well, you owe the president an apology, because as you know very well, your campaign, Sidney Blumenthal — he's another real winner that you have — and he's the one that got this started, along with your campaign manager, and they were on television just two weeks ago — she was, saying exactly that. So you really owe him an apology. You're the one that sent the pictures around your campaign — sent the pictures around with President Obama in a certain garb. That was long before I was ever involved, so you actually owe an apology.

Can you make any sense of that?

Trump was responding to Clinton saying he had peddled the "racist lie that President Obama was not born in the United States of America." A reporter has accused Clinton confidant Blumenthal of spreading the story back in 2008, but Trump didn't really drive that home at all.

And then he shifts to the Clinton campaign — also in 2008 — allegedly passing around an image of Obama in Muslim garb. The Drudge Report at the time did say Clinton's aides were pushing the image, but Trump doesn't even describe the "garb" as Muslim. Reporters will know what he was referring to, but does anyone else?

Another example was the Obama administration's "red line" in Syria:

TRUMP: First of all, she was there as secretary of state with the so-called line in the sand, which...

CLINTON: No, I wasn't. I was gone. I hate to interrupt you, but at some point...

TRUMP: Okay. But you were in contact — excuse me. You were...

CLINTON: At some point, we need to do some fact-checking here.

TRUMP: You were in total contact with the White House, and perhaps, sadly, Obama probably still listened to you. I don't think he would be listening to you very much anymore.

Obama draws the line in the sand. It was laughed at all over the world what happened.

First off, Trump misstates the "red line" as "line in the sand." Second, he doesn't even mention Syria or chemical weapons. Third, Clinton was still secretary of state when the line was drawn, but she wasn't when Syria President Bashaar al-Assad was reported to have crossed it by using chemical weapons on his own people.

Clinton successfully interrupts and derails Trump's attack here, and he's never able to get it back on track — either because he doesn't have his facts down or he's not nimble enough to do so.

Trump is a bare-knuckle campaigner, and his crowds at rallies eat up his attacks on Clinton. But for the casual viewers — who are more likely to be undecided voters — tuning in to Sunday's debate, his attacks were often nonsensical and incomplete.

If you're going to go down this road, you better be prepared and able to have your attacks down pat in advance. Trump didn't do it.

Read more:

Fact-checking the 2nd presidential debate

Donald Trump and Mike Pence's relationship just took a nose dive.