. . . if you don’t mind traveling back to Wednesday night (an eternity ago, I know).

1. Couple weeks back, someone on the news asked Giuliani — in an accusatory, offended tone — “So, will your keynote address at the Republican convention be nasty toward Obama? Are you going to tear the bark off the Democrats, go monster-negative?” (I paraphrase.) Rudy answered, both coolly and charmingly, “There will be comparisons.”

I loved that — and looked very much forward to the speech. Which was A-1 terrific.

2. They say Rudy “looks like an undertaker.” So, maybe he does — but a formidable and interesting undertaker.

3. I noticed he was wearing an American-flag lapel pin. And that reminded me: Where does Obama stand on that at the moment? Is it on, off — what’s he saying, and what’s he wearing?

4. I had to smile when Giuliani said this: “Every four years, we are told that this presidential election is the most important election of our lifetime. This year — 2008 — is the most important!”

A lot of us, indeed, say that every four years — I mean, all of it: “Every four years, people say this is the most important election. Actually, this year, it’s true.”

I imagine those words will trip from my lips in 2012, too — and 2016, and . . .

(Actually, I think you could make a greater case for 2004 — the Iraq War, according to some reports, is virtually won. And assorted machinery for the broader War on Terror is increasingly in place.)

5. Those chants of “U-S-A, U-S-A” — harmless, I know, but awfully jingo.

6. Said Rudy, “You’re hiring someone to do a job — an important job that involves the safety and security of your family. Imagine that you have two job applications in your hand . . .”

That reminded me, that’s what Bill Clinton has always said (or close to it): Every campaign is a job interview.

7. Was wondering: Has Rudy’s lisp become more pronounced? Or has it always been that way?

8. Loved the incredulous sarcasm with which Rudy pronounced the words “community organizer.” For months, people all over the country have been asking, “What the hell is a community organizer? Don’t you just appoint yourself one?”

(“Incredulous sarcasm” may not be the perfect description, but I trust you know what I’m driving at.)

9. “Then he ran for the state legislature — where nearly 130 times he was unable to make a decision yes or no. He simply voted ‘present.’ As mayor of New York City, I never got a chance to vote ‘present.’ And you know, when you’re president of the United States, you can’t just vote ‘present.’ You must make decisions.”

I have quoted the prepared text. And Rudy went off-text a little, improvising, riffing: “Oh, I just can’t make a decision — I don’t know whether to vote yes or no. It’s just too tough.” He was incredibly merry when he was saying all this — enjoying himself, cracking himself up, cracking up the audience. A mischievous delight ran through the hall.

10. “The choice in this election comes down to substance over style. John has been tested. Barack Obama has not.”

Very, very stark. And that’s what they said about Carter and Reagan, in 1980. It failed on the Democrats. But the thing was: Reagan had substance, tons of it.

11. At one point, Rudy whooped — don’t know if that worked.

12. The speech got a little — a little — loose and flabby, but not seriously so.

13. I say again: Rudy enjoyed himself, all through. An exceptionally happy warrior, he.

14. Listen to the happy warrior on the attack: “Obama was going to take public financing for his campaign, until he didn’t. Obama was against wiretapping before he voted for it. When speaking to a pro-Israel group, Obama favored an undivided Jerusalem. Until the very next day when he changed his mind.

“I hope for his sake, Joe Biden got that VP thing in writing.”

Glorious, glorious.

15. And how about his 300-advisers riff? “Later, after discussing it with his 300 foreign-policy advisers, he changed his position and suggested that the U.N. Security Council could find a solution. Apparently, none of his 300 advisers told him that Russia has a veto on any U.N. action. Finally, Obama put out a statement that looked . . . well, it looked a lot like John McCain’s.

“Here’s some free advice: Senator Obama, next time just call John McCain.”

Fantastic, fab. Sarcasm is a tricky thing: You can’t let it get too heavy-handed. And Rudy stayed on the happy side of that line (as would Sarah Palin, directly after him).

16. The cameras often swept the “family boxes,” and I was thinking, “Lot of second wives, at this Republican convention. Some thirds, too!”

17. Toward his conclusion, Rudy said, “We are the party that believes in giving workers the right to work.” I was so glad to hear that — hadn’t heard it in ages. Was a fairly common refrain in the 1980s. And it’s worth remembering, and repeating.

18. Then, “[We are] the party that believes parents should choose where their children go to school.” Yes, yes, why not be identified with that? Why not be identified with a civil-rights cause of our time?

19. My friend and colleague, the sagacious Rick Brookhiser, not long ago said this: “Rudy is a liberal who hates liberals. John McCain is a conservative who hates conservatives.” There’s a lot of truth in that. Only Rudy is not all that liberal. And I wonder how conservative he would have been, or would be, in an office outside New York City (where he was plenty conservative — on crime, most prominently and crucially).

20. This man gave one of the most engaging, rollicking, and fun — yes, fun — speeches I can remember hearing. That’s if you’re a partisan Republican, of course. And even if you’re not — you might have gotten some sort of kick out of it.

Way to go, Rudy G. And, following Mike Bloomberg: Can’t you run for mayor again? You don’t want your gains reversed by some Dinkinsian Democrat, do you?