There are a lot of support levels in the US that need to be broken before we can call for significant downside let alone a crash. Besides, any significant market decline doesn't occur overnight and there would be plenty of volatility that would squeeze traders out of long-term shorts. I think it's more important to be focused on the here and now and manage risk accordingly. Keep an eye on my blog, I've written about a few other shorts on there and there are plenty more setting up but timing will always be key.