On May 19, JPMorgan Chase had an investor-day presentation and billionaire CEO Jamie Dimon had a lot to say about the economy, global trade, and investing. And much of it sounded negative.During the presentation, Dimon brought up the subject of U.S. stagflation -- the dreaded combination of ongoing inflation and economic recession at the same time. Policymakers generally try to keep inflation low and economic growth high. When they intervene, it usually sacrifices one to benefit the other. But when both inf ...