The Twin Cities and Denver will face a common challenge for the next five weeks. As host cities for the Republican and Democratic national conventions, both are girding for battle with "sleeping dragons" and other tools of mass disorder.

There's one significant difference. Denver's City Council is considering an ordinance to defang the dragons. Minneapolis and St. Paul are biding their time.

Denver City Council's public safety committee will vote today on an ordinance that would bar protesters from carrying items such as weighted PVC pipes, carabiners and quick-drying concrete.

These are the raw materials of the sleeping dragon -- a maneuver that can lock protesters into a human barricade, create traffic nightmares and produce chaos.

Denver's public safety committee chairman Doug Linkhart has strongly urged the ordinance's passage. "In other cities, [protesters are] not just handcuffing themselves to each other," he said, according to the Rocky Mountain News. "They put their handcuffs inside PVC tubes, which are inside concrete. They've figured out ways that keep the police from just using bolt cutters to cut them apart. They also use buckets of urine and feces and various noxious substances to pour on themselves or the police."

Denver's proposed ordinance -- supported by the police chief and the mayor -- would bar protesters from carrying any object that can be used to obstruct roadways, sidewalks or building entrances and would also ban possession of noxious substances.

One might wonder why Denver is so concerned about disorder. Barack Obama, the Democratic presidential nominee-to-be, has called for an end to the Iraq war and otherwise adopted a leftist's dream agenda. But anarchists and anti-globalists are not satisfied. One group, Recreate 68, has vowed to make the street clashes of Chicago's notorious 1968 Democratic convention "look like a small get-together" compared with the havoc that will erupt in Denver.

Another anarchist group, Unconventional Action, has vowed to "target" fundraisers, delegates' hotels and the city's transportation system.

Big-time bluster from a few harmless flakes?

Recreate 68 demonstrated in Seattle during the traumatic and destructive 1999 World Trade Organization protests there, and it plans a "massive presence" in Denver, according to Denver's CBS Channel 4 TV station. In Seattle, protesters barricaded intersections, kept terrified delegates holed up in their hotels, and drove the mayor to declare a state of emergency.

Here in the Twin Cities, anarchist groups have vowed to shut down highways, bridges and city streets in an effort to prevent GOP delegates from reaching the Xcel Center.

Some will say threats of disruption are overblown, because most protesters will be peaceful. But it takes only a tiny minority to create chaos. In Seattle, police estimated that a few hundred protesters engaged in property crimes or acts of violence, while the ACLU puts the number at several dozen, according to a 2000 report by the Seattle City Council. Nevertheless, their actions left the city reeling.

Determined protesters can easily create disorder, according to anarchist documents filed by the city of St. Paul along with its recent legal memorandum defending the time and route restrictions it has placed on convention protesters. You can disable a junker car, lock four demonstrators to it, and stall traffic for hours. Or you can bring PVC pipes and chains to a giant protest march, and then lock down in a major intersection.

As police officers struggle to cut through pipes fortified with wire or concrete, they will have to cope with crowds of fuming motorists. "Angry drivers can be even more dangerous than police under these circumstances," advises an anarchist document.

St. Paul police officials do not see a need for a Denver-style ordinance because they believe that existing laws such as those against obstructing traffic and disorderly conduct are sufficient, said spokesman Tom Walsh.

St. Paul City Council member Dave Thune agreed. "Protesters have been chaining themselves together since I was a protester in the '60's," he said. "We'll just deal with illegal acts when they happen."

Keep in mind that Denver may only be a warm-up act. The GOP convention will bring together what is presumably the anarchists' vision of the evil empire: the most concentrated collection of Republican leadership assembled in the last four years.

Will we be ready?

Katherine Kersten • kkersten@startribune.com Join the conversation at my blog, www.startribune.com/thinkagain.