What's the most tax-efficient way to invest in US Treasuries for a non-US investor?

I might be wrong, but my understanding is that

1. US treasury interest payments are not taxed for foreign investors (if held directly)
2. Dividends paid from a US bond ETF are subject to a dividend withholding tax but there is no capital gains tax (for foreign investors)

So does this mean an accumulating US bond ETF is not taxable for a foreign investor? Is there a way to hold US Treasuries in a simple easy way while being tax efficient?