/u/Mordeth kindly linked to a previous answer of mine. If you read that, you'll see that for the 17th century at least, the Netherlands (Dutch Republic) were a force to be reckoned with. During the Eighty Year's War, the Dutch army was the most state of the art and professional army in Europe. Innovations implemented by Maurice of Nassau (later Prince of Orange) contributed significantly to the 'military revolution' of the 17th century. On the seas too the Dutch were among the strongest nations. The Dutch Republic was a small nation, but it was incredibly wealthy and could buy its way into relevancy.

After the 17th century, Dutch power declined while other nations grew in power (England and France at first, Prussia/Germany later on). The location of the Netherlands was such that if any nation would occupy it, that nation would gain a significant advantage over the other powerful nations. England could use it as a foothold on the continent; France could use it to lock the English out of trade with the continent; Prussia/Germany could use it to put pressure on France. So if one nation would attempt to seize the Netherlands, the other nations would intervene to prevent that from happening. It is much like what happened in 1673, when the Holy Roman Empire and Spain assisted the Dutch Republic in defeating the French armies.

This 'balance of power', with the Netherlands stuck between three major powers, is what helped the Netherlands 'survive', so to speak. After the Napoleonic Wars the victors united the Netherlands with the Southern/Austrian Netherlands to form a larger, slightly stronger nation - so that any future attempts by France could more easily be resisted. Furthermore, the Netherlands officially became a neutral country, with its neutrality guaranteed by the major powers. All of this was intended to make the balance of power more secure. It worked quite nicely (apart from Belgium seceding) as the Netherlands' neutrality was not violated until the Second World War.