....apparently, its how you use it!
Military history is littered with events where a small force, by means of deception, better training/equipment, position or just plain cussedness, held off superior forces.
Here are a few examples;
John.B.Magruder, during the Yorktown Peninsular Campaign, baffled 'Little Mac' by marching the few troops he had repeatedly across his front, thus fooling him into thinking that he faced much greater forces than were, in fact, present.
At Rorkes Drift, around 150 British troops held off an estimated 3000-4000 Zulu's. This was a vivid demonstration of what 'modern' weapons in the hands of trained and disciplined troops, in a fairly defendable position, were capable of.
In 1942, a small number of French Troops held the Bir Hakeim position against the mighty Afrika Korps and did much to upset Rommel's time-table.
During the battle of Waterloo, British troops held Hougoumont against repeated attacks throughout the day, albeit they were constantly fed reinforcements, but it did hold out until the end of the battle.
However, sometime, these heroic defences can have latter tragic consequences. For example;
The German defence of the Kholm pocket by around 5500 troops lasted for 105 days. the pocket survived by receiving supplies by airdrop, and its thought that this success led Goering into thinking that he could do the same again, but on a bigger scale, at Stalingrad. That, obviously, did not end well.
A very similar situation occurred during the French Indochina war, where the defenders of the Na San 'airhead' resisted all efforts of the Viet Minh to destroy them. Again, the French sustained this base by air supply, and thought that they could do the same again at Dien Bien Phu, resulting in a defeat that sparked the end of French Colonial rule in this area.
Nice Try, but No Cigar.
An early (1863) battle of the fledgling French Foreign Legion was that of Camerone, in Mexico where approximately 60 legionnaires held out for some time against around 3000 Mexicans.
And then you have the Alamo where, in 1836, some 250 defenders were more-or-less wiped out after resisting some 2000 enemy troops.
So, what other examples can folks think of?