Silly me for presuming that someone commenting about climate would actually understand radiative forcing...or be able to read a chart.

Radiative forcing is a change in the balance of energy fluxes in and out of the atmosphere. More energy in than out is a positive forcing and results in warming. Less energy in than out is a negative forcing and results in cooling. The chart details the changes in forcings acting upon the climate relative to the year 1750. If the bar representing a particular forcing extends to the right of 0 (positive), then it would be a positive (warming) forcing. If it extends to the left, then it is a negative (cooling) forcing.

Note the bar representing "Changes in Solar Irradiance". It's very short. Very little forcing change. Note the bar for CO₂. It's very long. Lots of forcing change. The bottom of the chart simply summarizes the net anthropogenic forcings by period. Those bars are very long and positive. What has caused modern warming? CO₂, not the Sun.