There's even a chapter titled "Poisonous Letter" in the Al Qaeda manual.
1-2	There's	_	_	_	_	_	_	_	_
1	There	there	PRON	EX	_	2	expl	2:expl	_
2	's	be	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	0:root	_
3	even	even	ADV	RB	_	2	advmod	2:advmod	_
4	a	a	DET	DT	Definite=Ind|PronType=Art	5	det	5:det	_
5	chapter	chapter	NOUN	NN	Number=Sing	2	nsubj	2:nsubj	_
6	titled	title	VERB	VBN	Tense=Past|VerbForm=Part	5	acl	5:acl	_
7	"	"	PUNCT	``	_	9	punct	9:punct	SpaceAfter=No
8	Poisonous	Poisonous	ADJ	NNP	Degree=Pos	9	amod	9:amod	_
9	Letter	Letter	PROPN	NNP	Number=Sing	6	obj	6:obj	SpaceAfter=No
10	"	"	PUNCT	''	_	9	punct	9:punct	_
11	in	in	ADP	IN	_	15	case	15:case	_
12	the	the	DET	DT	Definite=Def|PronType=Art	15	det	15:det	_
13	Al	Al	PROPN	NNP	Number=Sing	14	compound	14:compound	_
14	Qaeda	Qaeda	PROPN	NNP	Number=Sing	15	compound	15:compound	_
15	manual	manual	NOUN	NN	Number=Sing	2	obl	2:obl:in	SpaceAfter=No
16	.	.	PUNCT	.	_	2	punct	2:punct	_
