Where is Boeing going?

Twelve hundred jobs.

On the most basic level, that is what Washington state saves if Boeing builds its proposed 7E7 jet here.

If Boeing takes its next new airplane elsewhere, however, an economic engine that has powered Washington for more than half a century would begin to sputter and fail.

Many of the best and brightest minds in aerospace would follow the 7E7 out of the Puget Sound region. Scores of suppliers and subcontractors, and thousands more workers, would be next to go.

Boeing will manufacture popular 737s and 777s here for perhaps another 20 to 30 years. Eventually, though, when those models are taken out of production, local politicians and business leaders could face the daunting task of replacing tens of thousands of aerospace jobs.

Today in The Seattle Times, and for most of the next year, we'll walk our readers through the questions Boeing will be answering as it makes this milestone decision.

Why the 7E7 matters, or how 1,200 jobs could affect 200,000

Boeing says its 7E7 assembly line will employ just 800 to 1,200 people. But over the long term, losing the 7E7 could start a painful chain of events for an industry that, by some estimates, supports one in seven Puget Sound jobs.

Many of Boeing’s top engineers and managers would probably follow the 7E7 out of town. So would workers from major aerospace suppliers, who would be required to locate near the 7E7 assembly line.

Boeing’s 737 and 777 jets would remain here, but the models that replace them would almost surely be built in cutting-edge factories close to the 7E7 rather than in outdated plants in Washington.

Eventually, the question would be: Why have Boeing’s commercial-airplanes headquarters and research here if the manufacturing is elsewhere?