The Republican National Convention doesn't start until next Monday, but the first sign that we are living in troubled times went up across from the Xcel Energy Center two weeks ago:

"Our Political Agenda: Food, shelter and dignity."

But it's not a political sign. It's more a statement of faith.

The sign adorns the Dorothy Day Center, a shelter for homeless people in the shadow of the arena where John McCain will accept the presidential nomination and delegates, demonstrators and media will converge in a perfect storm of politics, protest and poverty.

Neither party seems able to address the realities of poverty represented by a growing homelessness problem. In Denver, where Democrats are meeting this week, there have been reports that officials offered free movie tickets to the homeless to get them off the streets and free haircuts to make them feel sharp when Obama comes to town.

Here in the Twin Cities, officials aren't trying to make the homeless feel sharp. Just safe.

About 200 people use the Dorothy Day shelter every night, and 300 or more eat meals there. They can't hide from the convention. It will be on their doorstep, as will thousands of protesters and police. So the center has tried to prepare for every possible problem, including clouds of tear gas and broken windows. There's even an evacuation plan.

"It's like we think a tornado is coming," says the Rev. John Estrem, head of Catholic Charities, which runs the Dorothy Day Center. "We want to make sure our clients have a place where they can be as safe and dignified as possible."

If a tornado does hit St. Paul, Dorothy Day will be at ground zero. Early in the planning process, several homeless service centers in St. Paul thought about relocating temporarily. But in the end, they decided to stay and to keep serving.

"It was a delicate issue," says Rosemarie Reger-Rumsey, director of the Listening House, a drop-in center two blocks from Dorothy Day. "We knew some folks would ask why we couldn't make it [a move] permanent. So we decided to stay: Our clients may be 'homeless,' but this is their neighborhood, their community and their neck of the woods. Uprooting them would be no more fair than if you did that to any other neighborhood."

The Twin Cities are popping veins trying to show off as Shangri-La on the Upper Mississippi, as devoid of big-city problems as we are of big-city bagels. But the truth is there are 7,000 homeless here, and the number is growing. And their "home," too, is being invaded. At a recent meeting of homeless people and police -- called to discuss the convention -- one homeless person told the cops not to take any guff from the protesters: "They're going to be right on our front porch," he said. "How much BS are you going to put up with?"

Reger-Rumsey worries many of the homeless -- those with mental illnesses or traumatic brain injuries -- might feel under siege during the convention, especially "if they're fenced in and surrounded by protests, noise and crowds." Those who choose, she said, can ask for a bus token and move, for the week, to another shelter in Minneapolis.

The Dorothy Day Center will extend its hours, remaining open to clients around the clock, and is adding breakfast to its normal meal schedule of lunch and dinner. With virtually nowhere to go outside the center during the convention, the idea is to make the center more accessible during the week. Still, it will be like living next to a foundry.

For those who stay, the convention will mean many inconveniences:

New clients will not be accepted at Dorothy Day until the convention ends. Current clients must remove bicycles -- many ride bikes to jobs or to run errands -- from the exclusion zone. Buses will be hard to get to, there will be no sleeping or lingering outside, no belongings left unattended, and any backpack or wheelchair or other item is likely to be searched, using dogs as well as metal detectors, inside the area. Tarps also have been strung inside the fences at Dorothy Day to screen the courtyards from outsiders.

Some have begun to feel like prisoners.

"We have to go on standstill, just because of those people," said Kelon Kilgore, 28, nodding across West Seventh Street towards the Xcel, where a GOP elephant, rampant, adorns the glass front. "When they put those tarps up, we knew what they thought about us. It's about making the city pretty. That's what it's all about."

Estrem says the tarps protect the clients. It's "a fragile population," he says, one that didn't ask to be at the center of the political and media universe.

"We're not trying to hide them; nor are we trying to put them on display. We have a fundamental belief in the dignity of every human person, and we are trying to get people to hear the voices of the poor.

"Frankly, they are hardly ever heard by anyone in our political system."

My view: It's a good thing that the homeless will be on hand as some of the most powerful and privileged people in America gather across West Seventh.

It could prove beneficial -- for people on both sides of the street.