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Cultivated Tulips have limited defenses. They have relatively stiff stems that help resist wind, and generally (although not always) closed petals that don’t get shaken about. However, they are bred for beauty, not for "toughing it out", and so overall they are quite delicate. Insects, viruses, fungi, and similar factors are always a risk (although bulbs purchased from a reputable seller and planted in clean soil should reduce the danger here). Deer are another common issue as they will eat the blooming heads right off! All of this is to say that, if planting at home, you will want to think about your environment and take precautions where necessary.
In the wild, things get a bit more interesting. Tulips out on in the high plains of central Asia have evolved to survive in their local climates - typically cold, mountainous regions. They deal with wind by having relatively lower stems, and tightly closed petals. And they can typically survive insects simply by way of being well spread out and having few natural predators. Bees also love them, as the heart of the flower (inside the petals) serves as a point of warmth where pollen-searching bees can spend a cold night.