diff --git a/ch07.asciidoc b/ch07.asciidoc
index 0da79b18..4227e29b 100644
--- a/ch07.asciidoc
+++ b/ch07.asciidoc
@@ -375,7 +375,7 @@ Median-Time-Past is specified in https://github.com/bitcoin/bips/blob/master/bip
 [[fee_sniping]]
 ==== Timelock Defense Against Fee-Sniping
 
-Fee-sniping is a theoretical attack scenario, where miners attempting to rewrite past blocks "snipe" higher-fee transactions from future blocks to maximize their profitability.
+((("scripting", "timelocks", "defense against fee-sniping")))((("timelocks", "defense against fee-sniping")))((("fee sniping")))((("security", "defense against fee-sniping")))((("sniping")))Fee-sniping is a theoretical attack scenario, where miners attempting to rewrite past blocks "snipe" higher-fee transactions from future blocks to maximize their profitability.
 
 For example, let's say the highest block in existence is block  #100,000. If instead of attempting to mine block #100,001 to extend the chain, some miners are attempting to re-mine  #100,000. These miners can choose to include any valid transaction (that hasn't been mined yet) in their candidate block  #100,000. They don't have to re-mine the block with the same transactions. In fact, they have the incentive to select the most profitable (highest fee per kB) transactions to include in their block. They can include any transactions that were in the "old" block  #100,000, as well as any transactions from the current mempool. Essentially they have the option to pull transactions from the "present," into the rewritten "past" when they re-create block  #100,000.