NRA USA Estate Tax (stocks, ETFs...) + Life Insurance: is a simple Life Insurance policy enough?

NRA USA Estate Tax (stocks, ETFs...) + Life Insurance: is a simple Life Insurance policy enough? Foreign national currently living in the USA: I'm trying to understand whether a simple life insurance policy is enough for an NRA (non-resident alien according to domicile test) with US-situs investments (over $60k in stocks, ETFs, etc.) to "protect" against the feated US Estate Tax (up to 40% of all assets held in the country upon death), or if life insurance proceeds on the life of a NRA are generally treated as well as US property for US estate tax purposes. So, for example, if a NRA has $100k in US stocks/ETFs and a $40k life insurance policy, could the insurance simply be used by the surviving spouse to provide liquidity for the estate tax?