Oil edged closer to a bear market collapse as Wall Street banks raised the specter of a recession, while Saudi Arabia tried to assure investors that OPEC will avert a supply glut. Futures closed down 0.5% on Monday, a fourth straight daily decline that put crude within pennies of a 20% drop from late April. Saudi Energy Minister Khalid Al-Falih said Monday that recent volatility is “unwarranted" and predicted allied crude producers will continue efforts to avoid an oversupply for the rest of 2019. Al-Falih’s assurances weren’t enough to calm traders worried that simmering trade disputes wil...