On first look, the uniform worn by Pope Benedict XVI’s bodyguards — the colorful yellow and blue stripey uniforms, the red ostrich feather-plumed helmets, the tights and bloomers — might lead you to think your grandmother could take them on.

You would be gravely mistaken.

The Swiss Guards are renowned in the security community; they are the world’s smallest army, but have an excellent reputation, outstanding capabilities and a noble history. Although tiny in number, they are a force to be reckoned with — an elite, company-sized military force that has defended pontiffs for more than 500 years, a duty that has sometimes demanded bloodshed.

Trained and equipped to fight an armed enemy (should the need arise), they are like the American Marines at the White House and the Beefeaters guarding Buckingham Palace. The Swiss Guards stand watch throughout the Apostolic Palace from the Vatican’s exterior gates to the entrance to the Pope’s private apartments.

As in other elite military units, competition to join the Swiss Guard is fierce. Selection standards are extremely high — all recruits must be unmarried Roman Catholic males between the ages of 19 and 30 who are able to endure grueling 24-hour shifts.

To be selected, a candidate must also be at least 5-foot-8 and have completed military training in the Swiss armed forces.

Carrying on tradition, the selected recruits train to handle swords and the Guard's trademark weapon: a combination spear and battle-axe known as the halberd.

Armed only with Renaissance weaponry, this minuscule army successfully kept Nazi soldiers out of Vatican City during World War II as Germany occupied Rome.

While they still wear armor and carry antique weapons, it’s not all medieval warfare for the Swiss Guards. They must maintain a high degree of physical fitness and master modern weaponry, such as the H&K submachine gun and the SIG Sauer 9 mm pistol. To best protect the Pope, they also train at close-quarters fighting and tactical movement, as well as security and counter-terrorism techniques.

And battle-axe might not be the best tool to ward off religious fanatics determined to pass a message to the Pope or to threaten him, so the guards have also added tear gas and pepper spray to their arsenal.

Across the pond, during the first papal visit to the U.S. since Usama bin Laden accused the pope of leading a “new Crusade” against Muslims, the Swiss Guard will be joined by the very best from the United States as well.

The U.S. Secret Service, responsible for protecting foreign dignitaries alongside local Washington and New York law enforcement, will be providing Benedict XVI and President Bush the utmost protection.

Supervisory Special Agent Ed Donovan gave us the inside scoop that one lucky Secret Service Agent has the very important job of driving the Popemobile. The Secret Service has a long history of working with the Swiss Guard on previous Papal visits as well as presidential visits to the Vatican.

As the pope makes his way to New York this weekend, security measures will be rigorous, from airspace restrictions and blockaded waterways to streets being entirely shut down. Police helicopters will patrol the skies, and the waters will be protected by harbor units and scuba divers stationed in the East River.

While measures will be similar to Pope John Paul II’s visit in 1995, we will see on the streets a very visible uniformed police presence and bomb-sniffing dogs.

The security services have stressed that they are not aware of any specific threats to the pope during this visit, but they recognize that bin Laden was critical of the pontiff in his latest videotape.

While you may not see the Swiss Guard in their eye-catching garb or carrying their trademark halberds on this trip, that doesn’t mean they aren’t there. In fact, it was a plainclothes undercover Swiss Guard who shielded Pope John Paul II and saved his life during a 1981 assassination attempt. The Swiss Guards, undercover and incognito, are on duty to protect the pope at all times.

Allison Barrie, a security and terrorism consultant with the Commission for National Security in the 21st Century, has an M.A. from the King's College War Studies department and has just completed her Ph.D thesis with King's.

Allison Barrie consults at the highest levels of defense, has travelled to more than 70 countries, is a lawyer with four postgraduate degrees and now the author of the new book "Future Weapons: Access Granted"  covering invisible tanks through to thought-controlled fighter jets. You can click here for more information on FOX Firepower columnist and host Allison Barrie and you can follow her on Twitter @allison_barrie.