In fact a little demo might be in order. We and our close allies are the only countries that have actually stopped testing nuclear weapons. Everyone else does what they think they can ge away with and just denies it. The intellegence community in every country knows the truth but the public denials keep the political harm to near zero.
In that spirit, let's set off a tactical nuke of say 500 tons in Afaganistan at a barren spot that we control. Everyone will know what it was, but we will deny it. Call it a minor earthquake or something. It will send the right message.
I've got a better idea. Keeping with the spirit of our repeated "accidental" bombings of the taliban supply warehouses - cum - "Red Cross Centers", we send in a wave of Tomahawk cruise missiles targetted at some talibastard facilities. One of the Tomahawks has a nuclear weapon at its payload.
When the dust settles, we dust off our Standard Apology for Military Mishaps form, and fill in the "explanation" line with something like, "Due to enemy's refusal to accept our reasonable terms for peace, we have been forced to dip into our inventory of nuclear tipped cruise missiles, and exchange the payloads for conventional weapons charges. Somehow this one slipped throught the cracks. We're really sorry and all, etc., and we hope that the enemy will accept our reasonable terms for peace before we have another tragic accident. You know how things always seem to 'just happen', etc."