Perhaps, but until those supply chains are established and proven to be effective, one should address the way 97% of all fentayl enters the US today - e-packet from China.

Just because opponents will likely evolve their tactics in the future should not prevent one from mitigating their extraordinarily successful tactic that is running in the present.

In FY 2012, USPS handled about 27 million ePackets from China. This increased to nearly 500 million ePackets by 2017. (Thanks to that disastrous subsidy agreement in 2011)

None of our inspection agencies could cope with this volume. Remove the discount-from-China subsidy, this will automatically reduce the volume of all e-packets and thus will ameliorate the load on inspection agencies.