Taking America's pulse inside Sears Tower
It was a long way down.

Seventy flights, 1,400 steps.

Erin Frey took them one at a time in 2 1/2-inch heels, moving like a woman running from something.

After what happened Sept. 11, Frey had to prove to herself she could escape Sears Tower in an emergency, no time to lace up the Nikes. Her peace of mind depended on it.

So, for a fire drill in which she and five co-workers from the 70th floor descended non-stop to the lobby, Frey wore the highest heels she could find in the vast lineup under her desk.

The black leather shoes made her almost 6 feet tall. They were classy but plain, with narrow toes tapering to a square tip, and they click-click-clicked like a metronome down the length of Stairwell 1--one of only two that go from top to bottom of the colossal tower.

Frey, 28, was running from her demons. It wasn't easy working in America's tallest skyscraper, not even for roughly $70,000 a year. She cried for no reason. She had headaches, felt nauseated, trembled. Looking out her office window was like staring into the maw. Frey angled her chair so she couldn't see.

Finally, one day in October, she and some colleagues from the executive recruiting firm Heidrick & Struggles asked Mark Swiecionis, the life-safety coordinator at Sears Tower, to arrange an evacuation drill for them.

Frey's nickname for Swiecionis was Safety Man. He had become very popular. Within two months after Sept. 11, Swiecionis would supervise about 80 percent of the evacuation drills he normally conducts in a year, virtually all on demand.

Now it was Frey's turn.

Click-click-click she went on a 1,400-step personal journey, finishing it in style even after the only other woman in heels stopped to remove her shoes.

Standing in the lobby amid suits sipping lattes, Frey wobbled. Her breath came fast. Her legs shook uncontrollably.

She smiled.

"Eighteen minutes," Safety Man said.

On Sept. 12, 2001, Americans awoke to a new reality shaped by the horror of terrorism on U.S. soil and the realization that it could happen again. In the months that followed, our fears and anxieties, dreams and compromises played out in an acutely personal way in Chicago's Sears Tower.

With its many setbacks shouldering the sky, the mighty 29-year-old building at 233 S. Wacker Drive has become a symbol of American muscle and commerce, audacity and know-how. It is at once imposing and elegant, rising majestically over the city like carefully stacked building blocks.

To take the skyscraper's pulse--to pace alongside the solitary, anxious occupant of the 98th floor on the morning of Sept. 11; to make the rounds with a night watchman as he checks the color of the liquid hand soap in public restrooms; to ride out a rumor of the tower's imminent demise with a trembling chain-smoker--is to take the measure of America.

Do we have what it takes?

Is the cell phone charged and the gas tank full?