Mere months after passing the largest tax hike in modern Chicago history, Mayor Rahm Emanuel vows to hit residents with even higher property-tax bills, this time to bail out pension mismanagement by Chicago Public Schools officials – behavior tacitly endorsed by the Chicago Teachers Union.

Chicago teachers are striking. You may recall that they were demanding a 30 percent raise earlier this year, which would have spiked the average teacher’s salary to nearly six figures. But nobody seems to be talking about what this will do to a pension system already in trouble. Chicago teachers’ pension fund is woefully underfunded. According to new...