loom = 將臨難避

The main meaning of the verb to loom is to appear or stand over someone as a large or threatening object, for example: "Storm clouds loomed over the horizon" or "As they walked through the valleys, the mountains loomed above them". It is often now used in a more figurative way to mean that something bad/ominous (the government shutdown in this case) seems to be about to happen. A similar example would be: "The economy had been growing for years, but the threat of recession now loomed".