While there are no new bank failures in play, financial markets have traumatic memories from last Friday and last weekend. Better safe than sorry heading into 2 days without the ability to react defensively to any significant developments in the banking world. European shares are leading the flight to safety so far this morning and that's spilling over into Treasuries (in a good way for rates) even though US stocks are doing a much better job of holding their ground.
In the chart below, notices the sharpest move and biggest retracement of yesterday's range in Germany's DAX equities index. While it's not pictured, EU sovereign debt is following in lock step with lower yields, and that's pulling US yields lower to start the day. US stocks are trying to rise above it all, and are actually doing an OK job so far. If they end up acquiescing to the flight-to-safety, it would likely only help Treasuries.