Historically humans get serious about avoiding disasters only after one has just struck t

Historically, humans get serious about avoiding disasters only after one has just struck them. 【B1】 that logic, 2006 should have been a breakthrough year for rational behavior. With the memory of 9/11 still 【B2】 in their minds, Americans watched hurricane Katrina, the most expensive disaster in U.S. history, on 【B3】 TV. Anyone who didn"t know it before should have learned that bad things can happen. And they are made 【B4】 worse by our willful blindness to risk as much as our 【B5】 to work together before everything goes to hell.

Granted, some amount of delusion (错觉) is probably part of the 【B6】 condition. In A. D. 63, Pompeii was seriously damaged by an earthquake, and the locals immediately went to work 【B7】, in the same spot—until they were buried altogether by a volcano eruption 16 years later. But a 【B8】 of the past year in disaster history suggests that modern Americans are particularly bad at 【B9】themselves from guaranteed threats. We know more than we 【B10】 did about the dangers we face. But it turns 【B11】 that in times of crisis, our greatest enemy is 【B12】 the storm, the quake or the 【B13】 itself. More of ten, it is ourselves.

So what has happened in the year that 【B14】 the disaster on the Gulf Coast？ In New Orleans, the Army Corps of Engineer has worked day and night to rebuild the flood walls. They have got the walls to 【B15】 they were before Katrina, more or less. That"s not 【B16】, we can now say with confidence. But it may be all 【B17】 can be expected from one year of hustle (忙碌).

Meanwhile, New Orleans officials have crafted a plan to use buses and trains to 【B18】 the sick and the disabled. The city estimates that 150,000 people will need a 【B19】 out. However, state officials have not yet determined where these people will be taken. The 【B20】 with neighboring communities are ongoing and difficult.

【B1】

A．To

B．By

C．On

D．For