Ice and slush closed in on the Coast Guard patrol craft as it crawled along a desolate coal and oil pier off the Chesapeake Bay. It was dusk, snowing and freezing, and in the black water ahead the bay barely rippled.
"If we saw someone out here, we'd stop by and talk to them, ask them what they're doing, where they hail from, ask them whether they're aware it's 25 degrees out," Petty Officer Trey Bennett said.
"Before everything happened," he said, "you'd figure someone was fishing. Now, you look and think, you wonder what he's doing, especially under bridges."
This, in its rawest form, is homeland security - an exercise built on patience and endurance that repeats itself 24 hours a day in the waters off Baltimore's harbor and elsewhere along 95,000 miles of U.S. coastline.
With counter-terrorism its new mission, the Coast Guard, known mostly for saving people lost at sea, is poised to become the heart of the new Homeland Security Department, more of a military force than ever in its two-centuries-long history.
Department officials, who fought to gain control of the Coast Guard, are building up the service's weapons, fleet and intelligence capabilities.
They have created Coast Guard SWAT teams that slide down ropes from helicopters and armed "sea marshals" who patrol waterways. And they have passed out new uniforms of black boots and military cargo pants to replace the relaxed blue chinos and rubber-sole shoes that Coast Guardsmen wore for decades.
The Coast Guard, which makes up more than one-fourth of the new department, has been responsible for protecting the nation's coastlines since Treasury Secretary Alexander Hamilton ordered 10 cutters into the water to enforce tariff laws in 1789.
But now, border security has assumed urgent new importance. And the Coast Guard, as part of the armed services and intelligence apparatus, will lend the Homeland Security Department much-needed muscle.
That's because the department, which is made up of 22 agencies, has little independent authority. It relies on the CIA, FBI, the National Security Agency and others for intelligence and depends on state and local law enforcement to act on its threat warnings.
The Coast Guard is the department's one exception. Fast becoming the department's own mini-army, the Coast Guard will soon have enhanced abilities to collect its own intelligence and respond to chemical or biological attacks with its own trained teams. It will have more resources for its boats, planes, helicopters and even armed SUVs.
What's more, those stepped-up duties are controlled directly by Tom Ridge, the secretary of homeland security.
Ridge said recently that the Coast Guard is "probably one of the most undervalued and under-appreciated assets in this federal government," stressing, as he often does, that the Guard is leading the way in homeland security.
Not since the 1930s has the Coast Guard been this popular, said the Guard's historian, Dr. Robert Browning.
"We were in the news constantly because of the rum runners," Browning said, referring to the efforts to stem illegal alcohol during Prohibition. "There were children's books and all kinds of books written.
"Now," he said, the Coast Guard "is the one agency they can visually see protecting people. It gives people a sense of security."
It's an image Ridge wants to capitalize on. This year, under his department, the Coast Guard is slated to receive its largest budget increase since World War II.
Its higher profile is a stark change for an agency that for more than five decades suffered through budget shortages and, despite its presence in World War II and the Vietnam War, was often overlooked as the fifth member of the armed services.
Coast Guard employees - or Coasties as they call themselves - know the standard Navy joke: The Coast Guard never worries about sinking because it can just wade back to shore.
Even as it has tended to be overlooked, the Coast Guard has enjoyed one of the longest-running positive public images for any federal agency - that of heroic saviors barreling through a hurricane behind a thick orange stripe, risking their lives to save someone else's.
That image has carried over to the fishing industry. The Coast Guard has built a reputation for keeping the playing fields fair through its patrols of national fisheries, ensuring they are not looted in off-hours or depleted of young fish.
One of its strengths has been its ability to juggle multiple responsibilities. On average each day, according to the Coast Guard, it saves 10 lives, conducts 109 search and rescue missions, seizes $9.6 million in illegal drugs, patrols dozens of fisheries and responds to 20 oil or hazardous chemical spills.
Funding shortfalls in recent years have also meant that the coxswain who drives a boat and leads a crew is also the one who fixes the boat when it breaks and suits up to handle a chemical or oil spill when a tanker ruptures.
Coast Guard officials say they are grateful for the boost in new resources. But privately, some say they fret that their new role as armed guards - more law enforcer than rescuer - might keep fishermen from trusting them as much and could make boaters or sailors less likely to stop and chat about suspicious things they see on the water.
"The fact remains that it's not likely [a Coast Guard SWAT team] is going to get a whole lot of intelligence saying, 'Here are the bad guys, go get them,'" said Stephen Flynn, a former Coast Guard commander and homeland security analyst at the Council on Foreign Relations.
For as long as anyone can remember, Flynn said, "there will be a fisherman who sees something weird, and he sure won't call the FBI, but he'll call the Coast Guard because the Coast Guard rescues him once in a while and is there to protect his fisheries."
"If the only image [fishermen and boaters] have of the Coast Guard is that of a SWAT team, they're not likely to try to help them out," he said. "[The Coast Guard's] strength comes not from all this new training but from having them there with their presence, developing relationships."
Out on the Chesapeake Bay, the 27-foot patrol craft slows behind a small boat bobbing just outside the Baltimore harbor.
"Hmmm," Bennett mumbles. He turns to his crew members, two young coxswains in training.
"Is he a crabber?" he asks, testing them. "Is he a fisherman?"
"He can't be a crabber this time of year," says Boatswain's Mate Matthew Flynn.
"And he doesn't have any pots," adds Boatswain's Mate Wayne Stark.
Bennett looks pleased. For all the talk in Washington about armed patrols, high-tech gear and military-like patrols, Bennett wants to teach his crew that homeland security mostly involves a close understanding of the water and those on it.
A discussion ensues about the fine points of winter perch fishing in the Chesapeake. As Bennett's craft passes beside the fishing boat, the fisherman looks pleased to see them. He holds up yards of net. Bennett and the man share a knowing laugh at the man's poor luck.
"People like seeing us out here, especially on a day like today," he says. "You just never really heard about us before. It was always like, 'Hey, don't forget about us.'
"Now it's different. A lot more work has come down. I mean a lot more."