I'll admit it -- Monday's global market sell-off had me spooked.

One of the reasons I've been bullish on the 2008 prospects for Boeing has been the strength of the global economy. Much of what I learned at business school last year had to do with the notion that the rest of the world is growing in economic clout relative to the United States, meaning that there's less risk that an American recession would spill over into the rest of the world. If Americans buy fewer goods from China, that's OK, because there's growing demand in India to off-set it.

Given that, I'd look at the Boeing's orders backlog and feel pretty confident. Not only is it really big - 3,427 planes represents at least six years' worth of production - but it's also very diverse. More than 75 percent of the planes on order are headed to buyers outside the United States. Those airlines will feel some pinch, in a U.S. recession but their domestic and regional operations should be largely insulated from our troubles, I'm thinking.

And going a step further, of the 800-plus planes that were bought for the USA, about 250 are going to jet-leasing giants ILFC and GE Capital Aviation Service, which have customers all over the world. And another 100-plus are going to Southwest Airlines. Southwest, based on what I saw post-September 11, is a recession-resistant airline. If there's a recession, it's safe to assume corporate travel offices will be seeking out the best deals possible, and that's good for a low-fare carrier like Southwest.

So that leaves between 450 and 500 planes, maybe 15 percent of the total backlog, that seems potentially risky; a serious hit, but not fatal.

And then Airbus sales guru John Leahy backs me up, saying over the weekend that under a worst-case scenario, he thinks Airbus would see no more than 27 percent cancellations. Again, that's a serious hit, but even so, that would still leave Boeing with a more-than-comfortable backlog of 2,500 planes.

Then comes Monday's global meltdown, and all my optimism goes out the window. If there's financial turmoil in Europe and Asia too, that casts some doubt on a much wider segment of Boeing's backlog. Air travel falls, airline revenue drops, stock values drop, it gets harder for them to get financing, and they start thinking maybe they can't afford their new planes after all. The privately owned carriers start canceling orders, pessimism snowballs and state-owned carriers cancel a few, and pretty soon . . .

So what does Tuesday's dramatic Fed move do for aerospace? This is off the top of my head - and I've only had two cups of coffee this morning. But in no particular order, I'm thinking:

• A Fed move to inject liquidity into the system is a very good thing for Boeing's backlog. It means that airlines will be better-able to borrow the money they need so that - recession or not - they'll be able to pay for the planes they've ordered.
  

• New planes mean lower operating costs for airlines, and that should take some of the sting out of higher fuel prices and lower revenue.
  

• It will be interesting to see how this affects Delta's merger talks. It just got cheaper to refinance the debt on airlines' balance sheets; maybe someone will decide that they can go it alone after all. On the other hand, it also just got cheaper to borrow money to buy another airline's shares; maybe that will encourage some slow-movers to move forward. And don't forget private equity - if the players who already hold stakes in airline have access to cheap cash, maybe this will spur them to increase their holdings, and put more pressure on CEOs and boards to consolidate.
  

• I suspect this increases the odds of U.S. carriers - merged or not - getting into the new-airplane market this year. It's a tougher call. The fact that the Fed pushed rates down three-quarters of a point is a clear signal that Bernanke and Co. see a recession ahead. That means lower airline revenues for the next couple quarters. But with interest rates this low, some airlines CFOs will certainly be tempted to propose buying new planes and retiring some of aging gas-guzzlers they have in their fleets.
  

• And it makes it easier for Boeing to borrow money to fix its 787 problems. Recession or not, Boeing has to get that global assembly line clicking and its Dreamliners delivered, and the sooner the better. (If the Azerbaijanis are talking about 787 delays, you know things are serious.)
  

So that's the good news. The bad news is it's looking more and more like our subprime housing mess is going to rock the whole world. That's not particularly good news for a state like Washington that relies so much on trade.