Not wrong!
John, You need a little more depth to your analysis. Your chart shows debt owned by foreigners and I don't dispute that China owns over 20% of the foreign owned debt. But the grand total of foreign owned debt is about $5.5 trillion out of a total debt (foreign and domestic) slightly over $16 trillion. So China owning around 8% of the total debt is not far off.
We can't simply stop China from burning coal by fiat but as one of their major customers we can create incentives to reduce their coal burning. In many ways China is already ahead of the US in renewable energy.