The great rivalries, to paraphrase noted historian Eric “Otter” Stratton, require a really futile-and-stupid gesture be done on somebody’s part. And the Buffs are just the guys to do it.

Can’t steal Traveler? Fine.

Make off with his saddle.

Write a ransom note.

Tell the Men of Troy, “You want it back? You’re going to have to beat us, ya bums.”

When it’s USC Week, ban — OK, strongly discourage — the wearing of cardinal around Boulder from Sunday through Saturday. Easy peasy. Buffs faithful pretty much know that drill already.

Start a Twitter war with Will Ferrell. Give Matt Leinart the mother of all wedgies. Re-acquaint yourself with USC athletic director Mike Bohn, the former CU AD. Something. Anything. If you can’t come up with a reason to hate on Heritage Hall, give University Park a reason to hate on you. Light a match, cover your ears, and let the fireworks fly.

“I think they should point to USC and say, ‘You are our rival,’” former CU quarterback and Fox Sports analyst Joel Klatt suggested. “Like CU did at a certain point with Bill McCartney and Nebraska. I think that becomes important.”

Can we be real CU fans? A decade into this Pac-12 arrangement, this we-hate-Utah-because-Larry-Scott-told-us-to vibe ain’t sticking. The Buffs-Utes “rivalry” feels like an arranged marriage of geography and political convenience, the new guys being told to go play in the corner and leave the rest of the cool kids alone.

It’s time to cowboy up against the coolest kid on the block.

Yeah, it sounds crazy. But they said McCartney was nuts, too, four decades ago, when he threw a metaphorical spitball at the Nebraska Cornhuskers — at a time when the Big Red was Alabama North and not Purdue West — and drew a line just east of Alvin, daring Nebraska coach Tom Osborne to cross it.

From 1962-81, a generation, Nebraska won or shared 11 Big Eight titles. The Buffs split one, in 1976, over that same span. In the summer of 1982, the Big Red had beaten CU 14 consecutive times and 19 out of 20. In four scraps from 1978-81, Nebraska had thumped CU by an average score of 49-8.

While Osborne seemed mildly bemused by the whole thing, the way a big brother is whenever baby brother declares war, McCartney was deadly serious.

Even if his own staff thought it was a little loopy, even if the hate was completely one-sided initially, it got to the point where Buffs players believed it. Not only believed it, but passed that hate down from class to class like a cherished heirloom.

“It was a daily mission,” former CU All-American wideout Michael Westbrook told me. “When we were in the weight room or in recruiting meetings, it was, ‘How are we going to beat Nebraska?’”

It took five seasons, and a lot of baking that hate into a program’s DNA, but the worm eventually started to turn. In October 1986, CU beat Nebraska for the first time since 1967. The teams would split the next four matchups, with the Buffs winning back-to-back meetings in 1989 and 1990 — the program’s first consecutive victories over the Big Red since 1960 and 1961.

The trouble with chucking a recyclable at Oregon, which swings the Pac-12’s biggest stick, is that the Buffs don’t play the Ducks every autumn. And while Utah might share our border to the west, hard-core Utes prefer to save their best bile for BYU and the Holy War.

In terms of profile, USC is an ideal target for punching up: It’s got an iconic brand, regional cache, storied traditions, national championships, Heisman winners, pathos, and, like Nebraska, a fan base that’s lugging around all kinds of hubris.

And like the Huskers of old, they’ve also had the Buffs in a rear-naked choke, despite Clay Helton’s best efforts to loosen that grip. The Men of Troy are 14-0 all-time against CU, 9-0 since the Buffs became Pac-12 brethren. Although three of the last five showdowns have been decided by four points or less, including that gut-punch of a come-from-behind 35-31 Trojans victory at Folsom late last October.

“If I was Colorado, that’s the way I would do it,” Klatt said. “I would point to USC and say, ‘We’re going to compete with you on the recruiting trail, we’re going to compete with you on the field. You’re the benchmark of the Pac-12, and we’re coming after you.’”

Sometimes, you don’t know if you can win a dang fight unless you pick it. When Mac called out the Big Red, pundits harrumphed. Husker fans laughed.

Many of them still do. Until you point to the scoreboard.