Spider-silk is one of the strongest materials on Earth, so being compared to a spider web actually is a compliment to Israel. Secondly, this gaff proves that Nasrallah is nothing more than a bumbling idiot, an idiot who pushed his people into a pointless war they didn't want or need.
Spider silk is a fibre secreted by spiders. Spider silk is a remarkably strong material; the strongest naturally-occurring fiber known. Its tensile strength is comparable to that of high-grade steel — according to Nature (see reference below), spider silk has a tensile strength of roughly 1.3 GPa, while one source  lists a tensile strength for one form of steel at 1.65 GPa. However, spider silk is much less dense than steel; its ratio of tensile strength to density is perhaps 5 times better than steel — as strong as Aramid filaments, such as Twaron or Kevlar. In fact, a strand of spider silk long enough to circle the earth would weigh less than 16 ounces (less than 460 grams).